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Creating Cascading DropDownLists Using ASP.NET MVC 4 And JQuery

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Sometimes you need to display DropDownLists in your ASP.NET MVC views such that values in one DropDownList are dependent on the value selected in another DropDownList. The most common example of such a functionality is countries and states DropDownLists where based on a selected country you need to populate the states DropDownList. This article shows how such a cascading DropDownLists can be developed using ASP.NET MVC and jQuery.

Have a look at the following figure that shows two DropDownLists:

image

As you can see the country DropDownList contains a list of countries along with the first entry of "Please select". Upon selecting a country the states DropDownList displays the states belonging to the selected country. When the page is loaded the country DropDownList has "Please select" entry selected and states DropDownList is disabled. Upon selecting a country the states DropDownList is enabled so that state selection can be made. Clicking on the Submit button submits the form to an action method for further processing.

Begin by creating a new ASP.NET MVC4 project based on empty project template. Add Scripts folder to the project and place jQuery library into it. Then add HomeController to the Controllers folder. In a real world scenario you will get countries and states from a database. Here, for the sake of simplicity, we will use some hardcoded country and state values.

Now add the following action method to the HomeController:

public ActionResult Index()
{
  List<string> items = new List<string>();
  items.Add("Please select");
  items.Add("USA");
  items.Add("UK");
  items.Add("India");
  SelectList countries = new SelectList(items);
  ViewData["countries"] = countries;
  return View();
}

The above code shows Index() action method. Inside the Index() method a generic List of strings is created to hold country names and a few countries are added to it. The DropDownList HTML helper of ASP.NET MVC requires its data in the form of SelectList object. Hence a SelectList is created based on the countries List. The SelectList object is passed to the view using countries ViewData variable.

Next, add another action method to the HomeController as shown below:

public JsonResult GetStates(string country)
{
  List<string> states = new List<string>();
  switch (country)
  {
    case "USA":
      states.Add("California");
      states.Add("Florida");
      states.Add("Ohio");
      break;
    case "UK":
      //add UK states here
      break;
    case "India":
      //add India states hete
      break;
  }
  return Json(states);
}

As you can see the GetStates() action method accepts a string parameter named country and returns JsonResult. The GetStates() returns JsonResult because this method will be called using jQuery and states information is to be returned as JSON data. The GetStates() method contains a simple switch statement that adds a few states to states List based on the country value. Finally, the states generic List is returned to the caller using Json() method. The Json() method converts any .NET object into its JSON equivalent.

Now, add Index view to the Views folder and key-in the following markup to it:

<% using(Html.BeginForm("ProcessForm","Home",FormMethod.Post)){ %>
<div>Select Country :</div>
<%= Html.DropDownList("country", ViewData["countries"] as SelectList)%>
<br /><br />
<div>Select States :</div>
<select id="state"></select>
<br /><br />
<input type="submit" value="Submit" />
<%} %>

The Index view consists of a <form> that houses two DropDownLists. The country DropDownList is rendered using DropDownList HTML helper. The first parameter of the DropDownList() helper is the name of the DropDownList and the second parameter is the SelectList object containing DropDownList values. The second DropDownList is added as raw <select> element whose ID is state. Although the <form> is submitted to ProcessForm action this method is not described below as it's not directly related to the functioning of the DropDownLists.

Now, add a <script> reference to jQuery library and also add a <script> block in the head section of the view. Then write the following jQuery code in the <script> block:

$(document).ready(function () {
  $("#state").prop("disabled", true);
  $("#country").change(function () {
    if ($("#country").val() != "Please select") {
       var options = {};
       options.url = "/home/getstates";
       options.type = "POST";
       options.data = JSON.stringify({ country: $("#country").val() });
       options.dataType = "json";
       options.contentType = "application/json";
       options.success = function (states) {
       $("#state").empty();
       for (var i = 0; i < states.length; i++) {
         $("#state").append("<option>" + states[i] + "</option>");
       }
       $("#state").prop("disabled", false);
    };
    options.error = function () { alert("Error retrieving states!"); };
    $.ajax(options);
  }
  else {
    $("#state").empty();
    $("#state").prop("disabled", true);
  }
 });
});

The above code shows the ready() handler. Inside the ready() handler, you first disable the state DropDownList using prop() method. The prop() method sets the disabled DOM property to true and thus disables the state DropDownList. Then the change() method is used to wire change event handler of the country DropDownList. The change event handler will be called whenever selection in the country DropDownList changes. The change handler function first checks value selected in the country DropDownList. If it is other than "Please select", the code creates an options object. The options object holds various settings for the Ajax request to made to the server for retrieving the state values. The url property points to the GetStates() action method. The type property is set to POST indicating that a POST method will be used while making Ajax request. The data property contains JSON representation of the country selected in the country DropDownList. Note that the name of this property has to match with the name of the GetStates() method parameter. The dataType and contentType are set to json and application/json respectively. These properties indicate the data type of the response and request respectively.

The success handler function is called when the Ajax call to GetStates() is successful. The success handler function receives the states returned from the GetStates() method as an array of JSON objects. Inside the success handler you iterate through the states array and add <option> elements to the state DropDownList using append() method. Before appending the newly fetched states the state DropDownList is emptied. Once t he states are populated the disabled property of the states DropDownList is set to true using prop() method.

The error handler function simply displays an error message in an alert dialog.

Finally, an Ajax call is made using $.ajax() method of jQuery and the options object is passed as its parameter.

That's it! Run the application and test whether states are populated as expected.

posted Oct 5, 2016 by Shivaranjini

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In Part 1 and Part 2 of this article series you developed a wizard in an ASP.NET MVC application using full page postback and Ajax helper respectively. In this final part of this series you will develop a client side wizard using jQuery. The navigation between various wizard steps (Next, Previous) happens without any postback (neither full nor partial). The only step that causes form submission to the server is clicking on the Finish wizard button.

The jQuery version of the wizard uses only one view - Index - that contains all the three steps as three <div> elements. Using jQuery code you show only one <div> at a time giving a wizard appearance to the view.

The HomeController class now contains two overloads of Index() action method as shown below:

public class HomeController : Controller
{
  public ActionResult Index()
  {
    return View();
  }

  [HttpPost]
  public ActionResult Index(Customer obj)
  {
    if (ModelState.IsValid)
    {
      NorthwindEntities db = new NorthwindEntities();
      db.Customers.Add(obj);
      db.SaveChanges();
      return View("Success");
    }
    return View();
  }
}

As you can see the second Index() method is marked with [HttpPost] attribute and accepts Customer parameter. Inside it checks whether there are any model state errors or not. In case of any errors Index view is returned otherwise data is added to the database and the Success view is returned.

Currently, there are no model validations on Customer class.  To add then using data annotations you can create a metadata class as shown below:

public class CustomerMetadata
{
  [Required]
  public string CustomerID { get; set; }
  [Required]
  public string CompanyName { get; set; }
  [Required]
  public string Address { get; set; }
  [Required]
  public string City { get; set; }
  [Required]
  public string Country { get; set; }
  [Required]
  public string PostalCode { get; set; }
  [Required]
  public string ContactName { get; set; }
  [Required]
  public string Phone { get; set; }
  [Required]
  public string Fax { get; set; }
}

[MetadataType(typeof(CustomerMetadata))]
public partial class Customer
{
}

As you can see the CustomerMetadata class defines all the properties that are accepted through the wizard. All the properties are marked with [Required] attribute. The CustomerMetadata class is linked with the Customer model class by creating a partial class and then decorating it with [MetadataType] attribute.

Now, add the Index view to the project. The Index view that contains all these <div> elements looks like this:

@model WizardInMVC.Models.Customer

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
</head>
<body>
@using (Html.BeginForm("Index", "Home", FormMethod.Post))
{
<div id="divBasic">
<h1>Step 1 : Basic Details</h1>
@Html.LabelFor(m=>m.CustomerID)<br />
@Html.TextBoxFor(m=>m.CustomerID)
@Html.ValidationMessageFor(m=>m.CustomerID)<br />
@Html.LabelFor(m=>m.CompanyName)<br />
@Html.TextBoxFor(m=>m.CompanyName)
@Html.ValidationMessageFor(m=>m.CompanyName)
<br />
<input type="button" name="nextBtn" value='Next' />
</div>
<div id="divAddress">
<h1>Step 2 : Address Details</h1>
@Html.LabelFor(m=>m.Address)<br />
@Html.TextBoxFor(m=>m.Address)
@Html.ValidationMessageFor(m=>m.Address)
<br />
@Html.LabelFor(m=>m.City)<br />
@Html.TextBoxFor(m=>m.City)
@Html.ValidationMessageFor(m=>m.City)
<br />
@Html.LabelFor(m=>m.Country)<br />
@Html.TextBoxFor(m=>m.Country)
@Html.ValidationMessageFor(m=>m.Country)
<br />
@Html.LabelFor(m=>m.PostalCode)<br />
@Html.TextBoxFor(m=>m.PostalCode)
@Html.ValidationMessageFor(m=>m.PostalCode)
<br />
<input type="button" name="prevBtn" value='Previous' />
<input type="button" name="nextBtn" value='Next' />
</div>
<div id="divContact">
<h1>Step 3 : Contact Details</h1>
@Html.LabelFor(m=>m.ContactName)<br />
@Html.TextBoxFor(m=>m.ContactName)
@Html.ValidationMessageFor(m=>m.ContactName)
<br />
@Html.LabelFor(m=>m.Phone)<br />
@Html.TextBoxFor(m=>m.Phone)
@Html.ValidationMessageFor(m=>m.Phone)
<br />
@Html.LabelFor(m=>m.Fax)<br />
@Html.TextBoxFor(m=>m.Fax)
@Html.ValidationMessageFor(m=>m.Fax)
<br />
<input type="button" name="prevBtn" value='Previous' />
<input type="submit" name="nextBtn" value='Finish' />
</div>
}
</body>
</html>

As you can see there are three <div> elements namely divBasic, divAddress and divContact. They contain various form fields for the respective wizard step. The markup shown above is essentially the summation of the markups in individual views from the Part 1 and Part 2 examples. This markup is quite straightforward. There is a minor change though - the Previous and Next buttons are of type button rather than submit. This is because these buttons no longer cause form submission. To turn the above markup into a wizard you need to write some jQuery code as shown below:

$(document).ready(function () {
  $("div").hide();
  $("div:first").show();
  $(":button").click(function () {
    var parentDiv = $(this).parent();
    $("div").hide();
    if($(this).val()=="Previous")
    {
      var prevDiv = parentDiv.prev();
      prevDiv.show();
    }
    if ($(this).val() == "Next") {
      var nextDiv = parentDiv.next();
      nextDiv.show();
    }
  });
});

As you can see the above jQuery code first hides all the <div> elements from the view. This is done using the element selector and hide() method. Then the first <div> element is made visible using :first selector and show() method. This way initially when the page loads only the first wizard step will be visible.

The code then wires event handlers for the click event of the Previous and Next buttons. This is done by selecting these buttons using :button selector and then using click() method. Notice that inside the click event handler nowhere we hardcode the IDs of various <div> elements. This way adding or removing a wizard step doesn't need any change in the jQuery code. Inside the click event handler, the code retrieves a reference to the parent <div> element of the button being clicked. This is done using parent() method called on this. The code then hides all the <div> elements. It then checks the button that was clicked - Previous or Next. If Previous button is clicked a reference to the previous <div> element is retrieved using prev() method called on parentDiv variable. Similarly if Next button is clicked, a reference to the next <div> element is retrieved using next() method called on parentDiv. Accordingly, either previous <div> or next <div> is displayed using show() method.

That's it! Test the wizard by running the application and then navigating between wizard steps.

READ MORE

Sometimes you need to select records for certain action using checkboxes. For example, you may select records for deleting and then delete them from the database. Consider the following screen shot that shows such an example in action.

image

As you can see there are two ways to select records for deletion:

  • You select checkboxes for rows to be deleted individually.
  • You can check the checkbox placed in the header row to select all the rows. This checkbox toggles the checked state of the other checkboxes.

Once selected you can click on the Delete Selected Customers button to actually delete the records.

Implementing such a functionality is straightforward using ASP.NET MVC, jQuery and Ajax. Let's see how.

As an example we will use Customers table of the Northwind database for this example. You will need to create a model class for the Customers table using EF code first. The Customer class is shown below:

public partial class Customer
{
    [StringLength(5)]
    public string CustomerID { get; set; }

    [Required]
    [StringLength(40)]
    public string CompanyName { get; set; }

    [StringLength(30)]
    public string ContactName { get; set; }

    [StringLength(30)]
    public string ContactTitle { get; set; }

    [StringLength(60)]
    public string Address { get; set; }

    [StringLength(15)]
    public string City { get; set; }

    [StringLength(15)]
    public string Region { get; set; }

    [StringLength(10)]
    public string PostalCode { get; set; }

    [StringLength(15)]
    public string Country { get; set; }

    [StringLength(24)]
    public string Phone { get; set; }

    [StringLength(24)]
    public string Fax { get; set; }
}

The NorthwindDbContext - the DbContext of our model - is shown below:

public partial class NorthwindDbContext : DbContext
{
    public NorthwindDbContext()
        : base("name=NorthwindDbContext")
    {
    }

    public virtual DbSet<Customer> Customers { get; set; }

    protected override void OnModelCreating
                (DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Customer>()
            .Property(e => e.CustomerID)
            .IsFixedLength();
    }
}

Notice that the NorthwindDbContext assumes that the database connection string is stored in web.config with a name of NorthwindDbContext.

Now add HomeController and write Index() and Delete() actions as shown below:

public ActionResult Index()
{
    using (NorthwindDbContext db = 
                  new NorthwindDbContext())
    {
        var query = from c in db.Customers
                    select c;
        return View(query.ToList());
    }
}

public ActionResult Delete(string[] customerIDs)
{
    using (NorthwindDbContext db = 
                        ew NorthwindDbContext())
    {
        foreach (string customerID in customerIDs)
        {
            Customer obj = db.Customers.Find(customerID);
            db.Customers.Remove(obj);
        }
        db.SaveChanges();
        return Json("All the customers 
                     deleted successfully!");
    }
}

The code from the Index() action simply picks all the customers from the Customers table and passes them to the Index view for display.

The Delete() action takes a single parameter - array of CustomerIDs to be deleted. The Delete() action will be called through client side jQuery code and while calling the array will be passed to it. The Delete() action simply iterates through the customerIDs array and one-by-one deletes the customers from the database. Finally, a success message is sent back to the caller in JSON format.

Now add Index view and also add a <script> reference to the jQuery library. Then add the following markup in the Index view.

@model List<SelectAllDeleteDemo.Models.Customer>
...
...
<body>
    <h1>List of Customers</h1>
    <input type="button" id="delete" 
         value="Delete Selected Customers" />
    <br /><br />
    <table border="1" cellpadding="10">
        <tr>
            <th><input type="checkbox" id="checkAll"/></th>
            <th>CustomerID</th>
            <th>CompanyName</th>
            <th>Country</th>
        </tr>
        @foreach(var item in Model)
        {
            <tr>
                <td><input type="checkbox" class="checkBox" 
                     value="@item.CustomerID" /></td>
                <td>@item.CustomerID</td>
                <td>@item.CompanyName</td>
                <td>@item.Country</td>
            </tr>
        }
    </table>
</body>
...

Notice a few things about this markup:

  • The customer data - CustomerID, CompanyName and Country - is displayed in a table.
  • The header row contains a checkbox whose ID is checkAll
  • Each table row contains a checkbox whose class attribute is set to checkBox. And its value is set to the CustomerID of that row.
  • The button above the table is used to initiate the delete operation and its ID is delete.

Now add a <script> block and write the following jQuery code:

$(document).ready(function () {

    $("#checkAll").click(function () {
        $(".checkBox").prop('checked', 
            $(this).prop('checked'));
    });

    $("#delete").click(function () {
        var selectedIDs = new Array();
        $('input:checkbox.checkBox').each(function () {
            if ($(this).prop('checked')) {
                selectedIDs.push($(this).val());
            }
        });

        var options = {};
        options.url = "/home/delete";
        options.type = "POST";
        options.data = JSON.stringify(selectedIDs);
        options.contentType = "application/json";
        options.dataType = "json";
        options.success = function (msg) {
            alert(msg);
        };
        options.error = function () {
            alert("Error while deleting the records!");
        };
        $.ajax(options);

    });
});

The code wires click event handlers for the checkAll checkbox and the delete button. The click event handler of the checkAll checkbox toggles the checked state of all the checkboxes. This is done by selecting the checkboxes using the jQuery class selector. The checkboxes whose class attribute is checkBox are matched and their checked property is toggled. Notice the use of prop() method to do this.

The click event handler of the delete button declares an array variable to store the selected CustomerIDs. It then selects all the checkboxes with CSS class of checkBox. The each() method iterates through these checkboxes. If a checkbox is checked its value is pushed into the array. This way we get all the CustomerIDs into the selectedIDs array. The success callback simply displays the success message returned from the Delete() action.

Then options object is created to hold all the Ajax configuration properties. Notice that url property points to the Delete() action and data property holds the JSON version of the selectedIDs array. Finally, $.ajax() is used to make the Ajax call.

That's it! Run the application and test the functionality.

READ MORE

One of my earlier articles (Creating Cascading DropDownLists using ASP.NET MVC 4 and jQuery) shows how to create cascading DropDownLists by making Ajax calls to the MVC action methods. While that approach is quite common and popular recently a reader asked whether something similar can be done without making any Ajax calls. If you want to implement cascading dropdownlists purely on client side then you will need to "eagerly load" all the data needed by them at the time of loading the page. This data can be stored in a hidden field and used as and when needed. Obviously this technique is not suitable for huge amount of data since everything is loaded at once on the client side. However, if the data is small and you understand the implications of loading it in advance here is how you can accomplish the task...

As an example we will use the same Country - Cities example. The entity data model for Countries and Cities table is shown below:

image

To hold the data that is to be sent to the client we create a POCO as shown below:

public class CountryCity
{
    public string Country { get; set; }
    public List<string> Cities { get; set; }
}

The CountryCity class has Country property that holds a CountryName from the database and the Cities property holds a List of CityName values. As mentioned earlier the data will be sent to the client in the form of a hidden form field. To store data in the hidden field we use JSON format. The code that does this job goes inside the Index action method and is shown below:

public ActionResult Index()
{
    LocationsDbEntities db = new LocationsDbEntities();
    var query = from c in db.Countries
                orderby c.CountryName ascending
                select new { 
                  CountryName = c.CountryName, 
                  Cities = c.Cities.ToList() };

    List<CountryCity> finalData = new List<CountryCity>();
    foreach (var country in query)
    {
        CountryCity obj = new CountryCity();
        obj.Country = country.CountryName;
        obj.Cities = new List<string>();
        foreach (var city in country.Cities)
        {
            obj.Cities.Add(city.CityName);
        }
        finalData.Add(obj);
    }
    string jsonData = JsonConvert.SerializeObject(finalData);
    ViewBag.LocationData = jsonData;
    return View();
}

The above code selects all the countries and their cities in an anonymous type using LINQ to Entities query. It then iterates through the results and forms a List of CountryCity objects. Once the whole List is formed it serializes that data into a string using Json.NET component. The SerializeObject() method of the JsonConvert class does that job. This string will hold the data in JSON format. This JSON data is then passed to the view using LocationData ViewBag property. A sample JSON data after serialization is shown below:

[
 {"Country":"USA",
  "Cities":["Redmond","Seattle"]},
 {"Country":"UK",
  "Cities":["London"]}
 {"Country":"India",
  "Cities":["Bangalore","Delhi"]}
]

The Index view that stores the LocationData ViewBag property into a hidden form field is shown below:

<form action="/home/processform" method="post">
    <input type="hidden" 
      id="locationdata" 
      name="locationdata" 
      value="@ViewBag.LocationData" />
    <select id="country" name="country"></select>
    <br /><br />
    <select id="city" name="city"></select>
    <br /><br />
    <input type="submit" value="Submit" />
</form>

As you can see the JSON data is stored in locationdata hidden form field. You will need to access this data for displaying it in the country and state dropdownlists. The jQuery code that does that is shown below:

<script type="text/javascript">
    var locationData;
    $(document).ready(function () {
        locationData = JSON.parse($("#locationdata").val());
        for (var i = 0; i < locationData.length;i++)
        {
            $("#country").append("<option>" + 
                          locationData[i].Country + 
                          "</option>");
        }
        $("#country").change(function () {
            var selectedCountry = $("#country").val();
            for (var i = 0 ; i < locationData.length; i++)
            {
                if(locationData[i].Country==selectedCountry)
                {
                    $("#city").empty();
                    for(var j=0;j<locationData[i].Cities.length;j++)
                    {
                        $("#city").append("<option>" + 
                                   locationData[i].Cities[j] + 
                                   "</option>");
                    }
                    return;
                }
            }
        });
    });
</script>

The above jQuery code declares a global variable - locationData - for storing the location data. The ready() function reads the hidden form field value and parses it into a JavaScript object using JSON.parse() method. A for loop then iterates through the locationData array and adds entries to the country dropdownlist using append() method.

The change() method wires the change event handler for the country dropdownlist. The change event handler iterates through the locationData array and finds the country matching the selection in the country dropdownlist. The code then retrieves cities for that country and populates the city dropdownlist.

That's it! Run the Index view and test whether it works as expected.

READ MORE

Most of the times ASP.NET MVC views are rendered as a result of user navigating to some action. For example, when a user navigates to /home/index in the browser (either through address bar or through a hyperlink), ASP.NET MVC executes the action method and usually returns a view to the browser. This means each view is rendered as a result of a full GET or POST request. At times, however, you may want to load views dynamically through Ajax. This way you can render contents of a view without full page refresh.

Consider the following page:

image

The above page consists of a table that lists customers from the Customers table of Northwind database. Each customer row has two buttons - Customer Details and Order Details. Clicking on the respective button should display customer details and order details from the database. Without Ajax you would have submitted the page back to the server and then returned a view with the corresponding details. Using Ajax you can display the details without causing any postback to the server. This is shown below:

image

As you can see the above figure shows order details for CustomerID ALFKI above the customers table. These details are fetched via Ajax request.

While displaying data through Ajax request you have two options:

  • Fetch raw data from the server and embed it in HTML markup on the client side
  • Fetch HTML markup with data embedded from the server

Although the choice of the approach depends on a situation, it can be said that the former approach is suitable to make calls to Web API or when HTML display is dynamically decided by the client script. The later approach is suitable when ASP.NET MVC strongly typed views (or partial views) are being used to render the UI. In this example we will be using the later approach.

To develop this example, create a new ASP.NET MVC application based on the Empty template. Then add ADO.NET Entity Data Model for Customers and Orders tables of Northwind database. The Customer and Order entities are shown below:

image

Next, add HomeController and write the Index() action method as shown below:

public ActionResult Index()
{
    using (NorthwindEntities db = new NorthwindEntities())
    {
        List<Customer> model = db.Customers.ToList();
        return View(model);
    }
}

The Index() action simply retrieves all the Customer entities from the Customers DbSet and passes them to the Index view.

Now, add another action method - GetView() - to the HomeController as shown below:

public ActionResult GetView(string customerID,string viewName)
{
    object model = null;
    if(viewName=="CustomerDetails")
    {
        using(NorthwindEntities db=new NorthwindEntities())
        {
            model = db.Customers.Find(customerID);
        }
    }
    if (viewName == "OrderDetails")
    {
        using (NorthwindEntities db = new NorthwindEntities())
        {
            model = db.Orders.Where(o => o.CustomerID == customerID)
                      .OrderBy(o => o.OrderID).ToList();
        }
    }
    return PartialView(viewName,model);
}

The GetView() action method accepts two parameters - customerID and viewName. These two parameters are passed through an Ajax request. Depending on the viewName parameter either CustomerDetails partial view is returned to the caller or OrderDetails partial view is returned. These two view need model in the form of a Customer object and a List of Order entities respectively. That's why model variable is declared as object. Once model variable is populated the partial view name and the model is passed to the PartialView() method. Here, we used partial views because the HTML output is to be inserted in an existing page through Ajax.

Next, add one view (Index.cshtml) and two partial views (CustomerDetails.cshtml and OrderDetails.cshtml) to the Home sub-folder of Views folder.

Add the following markup to the CustomerDetails.cshtml partial view:

@model MVCViewsThroughAjax.Models.Customer

<table border="1" cellpadding="10">
    <tr>
        <td>Customer ID :</td>
        <td>@Model.CustomerID</td>
    </tr>
    <tr>
        <td>Company Name :</td>
        <td>@Model.CompanyName</td>
    </tr>
    <tr>
        <td>Contact Name :</td>
        <td>@Model.ContactName</td>
    </tr>
    <tr>
        <td>Country :</td>
        <td>@Model.Country</td>
    </tr>
</table>

The above markup is quite straightforward. The CustomerDetails partial view simply displays CustomerID, CompanyName, ContactName and Country of a Customer in a table.

Now add the following markup to the OrderDetails.cshtml partial page:

@model List<MVCViewsThroughAjax.Models.Order>

<table border="1" cellpadding="10">
    <tr>
        <th>Order ID</th>
        <th>Order Date</th>
        <th>Shipping Date</th>
        <th>Shipped To</th>
    </tr>
    @foreach(var item in Model)
    { 
        <tr>
            <td>@item.OrderID</td>
            <td>@item.OrderDate</td>
            <td>@item.ShippedDate</td>
            <td>@item.ShipCountry</td>
        </tr>
    }
</table>

The above markup iterates through the List of Order entities and renders a table with four columns - OrderID, OrderDate, ShippedDate and ShipCountry.

Now, add the following markup to the Index view:

@model List<MVCViewsThroughAjax.Models.Customer>

...
<html>
<head>
...
</head>
<body>
    <div id="viewPlaceHolder"></div>
    <br /><br />
    <table border="1" cellpadding="10">
        <tr>
            <th>Customer ID</th>
            <th>Company Name</th>
            <th colspan="2">Actions</th>
        </tr>
        @foreach(var item in Model)
        {
            <tr>
                <td>@item.CustomerID</td>
                <td>@item.CompanyName</td>
                <td><input type="button" class="customerDetails" 
                           value="Customer Details" /></td>
                <td><input type="button" class="orderDetails" 
                           value="Order Details" /></td>
            </tr>
        }
    </table>
</body>
</html>

The Index view receives a List of Customer entities as its model and renders a table with CustomerID, CompanyName and two buttons - Customer Details and Order Details.

Now comes the important part - making Ajax calls to display customer details and order details. Noticed the <div> at the beginning of the body section? The viewPlaceHolder is where the output of CustomerDetails.cshtml and OrderDetails.cshtml will be loaded. To do so we will use load() method of jQuery. Here is how that can be done:

$(document).ready(function () {

    $(".customerDetails").click(function (evt) {
        var cell=$(evt.target).closest("tr").children().first();
        var custID=cell.text();
        $("#viewPlaceHolder").load("/home/getview", 
            { customerID: custID, viewName: "CustomerDetails" });
    });

    $(".orderDetails").click(function (evt) {
        var cell = $(evt.target).closest("tr").children().first();
        var custID = cell.text();
        $("#viewPlaceHolder").load("/home/getview", 
           { customerID: custID, viewName: "OrderDetails" });
    });
});

Recollect that Customer Details and Order Details buttons have assigned CSS class of customerDetails and orderDetails respectively. The above jQuery code uses class selector to wire click event handlers to the respective buttons. Inside the click event handler of Customer Details button, the code retrieves the CustomerID from the table row. This is done using closest(), children() and first() methods. The CustomerID is stored in custID variable. Then load() method is called on viewPlaceHolder <div>. The first parameter of the load() method is the URL that will be requested through an Ajax request. The second parameter is a JavaScript object that supplies the data needed by the requested URL. In our example, GetView() action method needs two parameters - customerID and viewName. Hence the object has customerID and viewName properties. The customerID property is set to custID variable and viewName is set to CustomerDetails.

The click event handler of Order Details is similar but loads OrderDetails partial view.

That's it! You can now run the application and try clicking on both the buttons. The following figure shows customer details loaded successfully.

image

Notice that through out the application run the URL shown in the browser address bar remains unchanged indicating that Ajax requests are being made to display customer details and order details.

In the above example Ajax requests were made to /home/getview action. A user can also enter this URL in the browser's address bar producing undesirable results. As a precaution you can check the customerID and viewName parameters inside the GetView() action method (not shown in the above code). If these parameters are empty or contain invalid values you can throw an exception.

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Some time back during one of my training programs I was asked this question by a beginner in ASP.NET MVC - "Can we have TempBag wrapper for TempData just as we have ViewBag for ViewData?"

Whether such a wrapper is needed or not is a different question but if you wish you can create one using dynamic objects of C# language. Here I am going to show a quick way to wrap TempData into our own TempBag and then using it in the controller and view.

The main class that does the trick is this:

public class MyTempBag : DynamicObject
{
    TempDataDictionary tempData = null;

    public MyTempBag(TempDataDictionary tempdata)
    {
        this.tempData = tempdata;
    }

    public override bool TryGetMember(GetMemberBinder binder, out object result)
    {
        try
        {
            if (tempData.Keys.Where(k => k == binder.Name).Count() > 0)
            {
                result = tempData[binder.Name];
                return true;
            }
            else
            {
                result = "Invalid TempBag Property";
                return false;
            }
        }
        catch
        {
            result = "Invalid TempBag Property";
            return false;
        }
    }

    public override bool TrySetMember(SetMemberBinder binder, object value)
    {
        try
        {
            tempData[binder.Name] = value;
            return true;
        }
        catch
        {
            return false;
        }
    }
}

The System.Dynamic namespaces provides DynamicObject class that can be used to create your own custom dynamic object. In order to create your own dynamic object using DynamicObject class you need to inherit it from DynamicObject and override three methods, viz. TryGetMember, TrySetMember and TryInvokeMember. The first two methods allow you to get and set dynamic properties whereas the last method allows you to invoke method calls on the dynamic object. In our specific case we don't need to implement TryInvokeMember because all we need is an ability to set and get properties.

The MyTempBag inherits from DynamicObject base class and accepts TempDataDictionary as its constructor parameter. The TrySetMember() method sets a TempData property value by using tempData variable. On the same lines, TryGetMember() method retrieves a TempData property value using the tempData variable.

Once you create MyTempBag class you can use it in the controller as follows:

public class HomeController : Controller
{
    dynamic TempBag = null;

    public HomeController()
    {
        TempBag = new MyTempBag(TempData);
    }

    public ActionResult Index()
    {
        TempBag.Message = "This is a test message";
        return View();
    }
}

The above code declares a dynamic variable - TempBag - inside the HomeController class. In the constructor of the HomeController this variable is set to a new instance of MyTempBag. Notice that TempData property of the controller is passed to the constructor of MyTempBag class. Once created the TempBag can be used as shown in the Index() action method.

In order to read the TempBag property inside a view you would write:

@{
    Layout = null;
    dynamic TempBag = new MyTempBag(TempData);
}

...
<html>
...
<body>
    <h3>@TempBag.Message</h3>
</body>
</html>

The view also creates an instance of MyTempBag and then reads the TempData property using TempBag object.

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In Part 1 of this article series you developed a wizard in an ASP.NET MVC application. Although the wizard developed in Part 1 works as expected it has one shortcoming. It causes full page postback whenever you click on Previous or Next button. This behavior may not pose much problem if a wizard has only a few steps. However, if a wizard has many steps and each step accepts many entries then full page postback can deteriorate the user experience. To overcome this shortcoming you can add Ajax to the wizard so that only the form is posted to the server. In this part of the series you will convert the application developed in Part 1 to use Ajax. In the next part you will further enhance the wizard using jQuery so that data is posted to the server only on the final step.

To convert the wizard application developed previously to use Ajax you will use Ajax helper of ASP.NET MVC. To use Ajax helper you need to make certain changes to the application. These changes are listed below:

  • All the four views namely BasicDetails, AddressDetails, ContactDetails and Success will now be partial views.
  • All the action methods will now return the corresponding partial views.
  • The wizard will be launched by Index view and initially BasicDetails partial view will be displayed.

You might wonder as to why we are making these changes. These changes are required since we wish to use Ajax helper. The Ajax helper allows you to submit a form using an Ajax request and the returned response is displayed in a DOM element. For example, you may create a form that makes a post request to an action method and displays a success message returned by the action method in a <div> element. In our specific case when one wizard step is submitted to the server using an Ajax request the server responds by sending the next or previous wizard step. Thus a form submits to the server and renders another form in the browser. This requires that the wizard steps return only the HTML needed to display that step and not the page level items such as <script> and <link>. The page level items just mentioned will go inside Index view that launches the wizard.

Ok. Let's begin our development. Add an Index view to the project and key-in the following markup into it:

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<script src="~/Scripts/jquery-1.10.2.js"></script>
<script src="~/Scripts/jquery.unobtrusive-ajax.js">
</script>
<title>Index</title>
</head>
<body>
<div id="divContainer">
  @Html.Partial("BasicDetails")
</div>
</body>
</html>

Notice the above markup carefully. The <head> section of the page contains <script> references to jquery-1.10.1.js and jquery.unobtrusive-ajax.js. These files are necessary for the proper working of Ajax helper. Also notice that the body section contains a <div> with ID of divContainer. This <div> plays an important role in the functioning of the wizard because it houses various wizard steps. As you can see from the code initially it hosts BasicDetails partial view.

Now add a Partial View and name it as BasicDetails. The BasicDetails partial view contains the following markup:

@model WizardInMVC.Models.BasicDetails


@{
AjaxOptions options = new AjaxOptions();
options.HttpMethod = "POST";
options.InsertionMode = InsertionMode.Replace;
options.UpdateTargetId = "divContainer";
}

@using (Ajax.BeginForm("BasicDetails","Home",options))
{
<h1>Step 1 : Basic Details</h1>
@Html.LabelFor(m=>m.CustomerID)<br />
@Html.TextBoxFor(m=>m.CustomerID)
@Html.ValidationMessageFor(m=>m.CustomerID)<br />
@Html.LabelFor(m=>m.CompanyName)<br />
@Html.TextBoxFor(m=>m.CompanyName)
@Html.ValidationMessageFor(m=>m.CompanyName)
<br />
<input type="submit" name="nextBtn" value='Next' />
}

The BasicDetails partial view has BasicDetails class as its data model. It creates an instance of AjaxOptions class. The AjaxOptions class is used to supply various configuration settings while using the Ajax helper. In this case we set HttpMethod, InsertionMode and UpdateTargetId properties. The HttpMethod property indicates the form submission method and it is set to POST in this case. The InsertionMode and UpdateTargetId properties are very important for us. The UpdateTargetId property indicates an ID of a DOM element that will be updated with the response returned from the server. In our example UpdateTargetId is divContainer, the <div> element you added inside the Index view. The InsertionMode property governs how the server response should be added to the UpdateTargetId. The InsertionMode has three possible values - InsertAfter, InsertBefore and Replace. In our example we wish to replace the whole content of divContainer with the response (i.e. a form making a wizard step) and we set it to Replece.

Then a <form> is rendered using Ajax.BeginForm() helper method. The BeginForm() method accepts three parameters viz. action method name, controller name and AjaxOptions object. Inside it contains the same markup as the earlier example (see Part 1 for more details).

On the same lines you need to add AddressDetails, ContactDetails and Success partial views. The complete markup of these partial views is given below:

AddressDetails

@model WizardInMVC.Models.AddressDetails

@{
AjaxOptions options = new AjaxOptions();
options.HttpMethod = "POST";
options.InsertionMode = InsertionMode.Replace;
options.UpdateTargetId = "divContainer";
}

@using (Ajax.BeginForm("AddressDetails","Home",options))
{
<h1>Step 2 : Address Details</h1>
@Html.LabelFor(m=>m.Address)<br />
@Html.TextBoxFor(m=>m.Address)
@Html.ValidationMessageFor(m=>m.Address)
<br />
@Html.LabelFor(m=>m.City)<br />
@Html.TextBoxFor(m=>m.City)
@Html.ValidationMessageFor(m=>m.City)
<br />
@Html.LabelFor(m=>m.Country)<br />
@Html.TextBoxFor(m=>m.Country)
@Html.ValidationMessageFor(m=>m.Country)
<br />
@Html.LabelFor(m=>m.PostalCode)<br />
@Html.TextBoxFor(m=>m.PostalCode)
@Html.ValidationMessageFor(m=>m.PostalCode)
<br />
<input type="submit" name="prevBtn" value='Previous' />
<input type="submit" name="nextBtn" value='Next' />
}

ContactDetails

@model WizardInMVC.Models.ContactDetails

@{
AjaxOptions options = new AjaxOptions();
options.HttpMethod = "POST";
options.InsertionMode = InsertionMode.Replace;
options.UpdateTargetId = "divContainer";
}

@using (Ajax.BeginForm("ContactDetails","Home",options))
{
<h1>Step 3 : Contact Details</h1>
@Html.LabelFor(m=>m.ContactName)<br />
@Html.TextBoxFor(m=>m.ContactName)
@Html.ValidationMessageFor(m=>m.ContactName)
<br />
@Html.LabelFor(m=>m.Phone)<br />
@Html.TextBoxFor(m=>m.Phone)
@Html.ValidationMessageFor(m=>m.Phone)
<br />
@Html.LabelFor(m=>m.Fax)<br />
@Html.TextBoxFor(m=>m.Fax)
@Html.ValidationMessageFor(m=>m.Fax)
<br />
<input type="submit" name="prevBtn" value='Previous' />
<input type="submit" name="nextBtn" value='Finish' />
}

Success

<h3>Customer Data Saved Successfully!</h3>
@Html.ActionLink("Add Another Customer","Index","Home")

Notice that all the partial views that use Ajax helper declare their own AjaxOptions object and pass it to BeginForm() method.

Once you create all the partial views modify the action methods to return partial view instead of view. The following code shows the modified BasicDetails() action method:

[HttpPost]
public ActionResult BasicDetails(BasicDetails data, 
string prevBtn, string nextBtn)
{
  if (nextBtn != null)
  {
    if (ModelState.IsValid)
    {
      Customer obj = GetCustomer();
      obj.CustomerID = data.CustomerID;
      obj.CompanyName = data.CompanyName;
      return PartialView("AddressDetails");
    }
  }
  return PartialView();
}

As you can see there is no change in the logic of the action method. The only difference is that instead of View() method it uses PartialView() method. Also change AddressDetails() and ContactDetails() action method to return partial views instead of views. If you run the wizard you will find that even after navigating to different wizard steps the URL in the browser's address bar remains unchanged indicating that Ajax requests are being made to the server rather than full page postback.

image

As you can see even if you are on Step 2 the address bar still points to /home/index.

That's it! In the next part you will learn to develop a wizard that replies more on client side technologies and posts data to the server only at the last step.

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At times you want to accept user input in your web applications by presenting them with a wizard driven user interface. A wizard driven user interface allows you to logically divide and group pieces of information so that user can fill them up easily in step-by-step manner. While creating a wizard is easy in ASP.NET Web Forms applications, you need to implement it yourself in ASP.NET MVC applications. There are more than one approaches to creating a wizard in ASP.NET MVC and this article shows one of them. In Part 1 of this article you will develop a wizard that stores its data in ASP.NET Session and the wizard works on traditional form submission.

To develop a wizard in ASP.NET MVC you will use the following approach:

  • Each wizard step will have an action method in the controller and a view.
  • The data accepted in each wizard step is stored in a view model class designed for that step.
  • All the action methods for wizard steps will accept three parameters - step's view model object and two string parameters indicating the Next / Previous status.
  • The action methods mentioned above grab the data from view model object and store it in Session till the final step.
  • The action methods return a view for the next step if Next button is clicked. If Previous button is clicked they return a view for the previous step and they return the same view if there are any model validation errors.
  • Model validations are checked only when Next button is clicked.

Now that you have some idea about the approach we will be taking for developing a wizard, let's create a sample application that illustrates how this approach can be implemented. Begin by creating a new ASP.NET MVC application based on Empty template. Then right click on the Models folder and add an ADO.NET Entity Data Model for the Customers table of Northwind database. The following figure shows the Customer model class in the designer.

image

As you can see the Customer class has several properties. For the sake of creating the wizard let's group them in three steps as follows:

  • Basic Details : Customer ID, CompanyName
  • Address Details : Address, City, Country, PostalCode
  • Contact Details : ContactName, Phone, Fax

Note that a few properties have been omitted from the wizard just to keep things tidy.

You need to create a view model class for each of the wizard steps outlined above. So, you need to add BasicDetails, AddressDetails and ContactDetails classes to the Models folder. These are simple POCOs as shown below:

public class BasicDetails
{
  [Required]
  public string CustomerID { get; set; }
  [Required]
  [StringLength(30)]
  public string CompanyName { get; set; }
}
public class AddressDetails
{
  [Required]
  public string Address { get; set; }
  [Required]
  public string City { get; set; }
  [Required]
  public string Country { get; set; }
  [Required]
  public string PostalCode { get; set; }
}
public class ContactDetails
{
  [Required]
  public string ContactName { get; set; }
  [Required]
  public string Phone { get; set; }
  [Required]
  public string Fax { get; set; }
}

As you can see the three classes namely BasicDetails, AddressDetails and ContactDetails contain only those properties that are relevant to the corresponding wizard step. Additionally, they use data annotations for basic validations. You can add more data annotations as per your requirement. For this example, the above attributes are sufficient.

Now, add HomeController to the Controllers folder. The HomeController contains five methods in all - Index(), GetCustomer(), RemoveCustomer(), BasicDetails(), AddressDetails() and ContactDetails(). The Index() action method and GetCustomers() / RemoveCustomer() helper methods are shown below:

public ActionResult Index()
{
  return View("BasicDetails");
}

private Customer GetCustomer()
{
  if (Session["customer"] == null)
  {
    Session["customer"] = new Customer();
  }
  return (Customer)Session["customer"];
}

private void RemoveCustomer()
{
  Session.Remove("customer");
}

The Index() action method simply returns a view that represents the first step of the wizard - BasicDetails. The GetCustomer() helper method does the job of retrieving a Customer object from Session and return it to the caller. The GetCustomer() method first checks whether a Customer object is stored in the Session or not. If Customer object exists that object is returned, otherwise a new Customer object is created and stored in the Session with a key customer. The RemoveCustomer() method simply removes the customer key and associated Customer object from the Session.

Each wizard step has an action method. Since this example has three wizard steps you need to add three action methods. The BasicDetails() action method is shown below:

[HttpPost]
public ActionResult BasicDetails(BasicDetails data, 
string prevBtn, string nextBtn)
{
  if (nextBtn != null)
  {
    if (ModelState.IsValid)
    {
      Customer obj = GetCustomer();
      obj.CustomerID = data.CustomerID;
      obj.CompanyName = data.CompanyName;
      return View("AddressDetails");
    }
  }
  return View();
}

The BasicDetails() action method accepts three parameters - BasicDetails object, prevBtn and nextBtn. The BasicDetails view posts the form to BasicDetails action method and hence it is marked with [HttpPost] attribute. The three parameters of BasicDetails() action method are passed in by the default model binding process of ASP.NET MVC. The BasicDetails object contains the values of CustomerID and CompanyName as entered on the BasicDetails view. Inside the BasicDetails() action method you need to know which of the two buttons (Next / Previous) was clicked by the user. That's why the two string parameters prevBtn and nextBtn are used. If prevBtn or nextBtn is not null it indicates it indicates that the button was clicked. The BasicDetails view doesn't have Previous button since it is the first step of the wizard. The BasicDetails() still accepts prevBtn parameter for the sake of consistency with other wizard step methods.

Inside, the code checks the ModelState.IsValid property to determine whether the the model contains valid data. If IsValid returns true GetCustomer() is called to retrieve the Customer object from the Session. The CustomerID and CompanyName properties of the Customer object are set with the corresponding properties of BasicDetails object and AddressDetails view is returned. If there are any model validation errors the BasicDetails view will be returned.

The AddressDetails() method works on the similar lines as that of BasicDetails() and is shown below:

[HttpPost]
public ActionResult AddressDetails(AddressDetails data, 
string prevBtn, string nextBtn)
{
  Customer obj = GetCustomer();
  if (prevBtn!=null)
  {
    BasicDetails bd = new BasicDetails();
    bd.CustomerID = obj.CustomerID;
    bd.CompanyName = obj.CompanyName;
    return View("BasicDetails",bd);
  }
  if (nextBtn != null)
  {
    if (ModelState.IsValid)
    {
      obj.Address = data.Address;
      obj.City = data.City;
      obj.Country = data.Country;
      obj.PostalCode = data.PostalCode;
      return View("ContactDetails");
    }
  }
  return View();
}

The AddressDetails view has Previous as well as Next button and posts to AddressDetails() action method. The AddressDetails() method accepts AddressDetails object and prevBtn and nextBtn parameters. If the Previous button was clicked, the code prepares an instance of BasicDetails object and populates its CustomerID and CompanyName properties from the Customer object from Session. The code then returns BasicDetails view with BasicDetails object as its model. This way user is taken to the previous step of the wizard.

Then the code checks whether Next button was clicked. If so, IsValid property of ModelState is checked as before. If there are no model validation errors data from AddressDetails object is stored in the Customer object from the Session. The code then return ContactDetails view.

The ContactDetails() action method does the job of saving the newly added Customer to the database and is shown below:

[HttpPost]
public ActionResult ContactDetails(ContactDetails data, 
string prevBtn, string nextBtn)
{
  Customer obj = GetCustomer();
  if (prevBtn != null)
  {
    AddressDetails ad = new AddressDetails();
    ad.Address = obj.Address;
    ad.City = obj.City;
    ad.Country = obj.Country;
    ad.PostalCode = obj.PostalCode;
    return View("AddressDetails", ad);
  }
  if (nextBtn != null)
  {
    if (ModelState.IsValid)
    {
      obj.ContactName = data.ContactName;
      obj.Phone = data.Phone;
      obj.Fax = data.Fax;
      NorthwindEntities db = new NorthwindEntities();
      db.Customers.Add(obj);
      db.SaveChanges();
      RemoveCustomer();
      return View("Success");
    }
  }
  return View();
}

The ContactDetails view posts to the ContactDetails() action method. The ContactDetails() action method accepts ContactDetails object and prevBtn and nextBtn parameters. As before, it checks whether the Previous button was clicked. If so, a new instance of AddressDetails class is created and is filled with the data from Customer object from the Session. The code then returns AddressView by passing AddressDetails object as its model.

If user clicks on Next button, model is checked for any validation errors using IsValid property. If there are no validation errors properties of Customer object stored in the Session are assigned values of the corresponding ContactDetails object properties. Then a Entity Framework context is instantiated and the Customer object is added to the Customers DbSet. Calling SaveChanges() saves the data to the database. RemoveCustomer() is then called so as to remove the Session object. Finally, Success view is returned from the method.

Next, add four views - BasicDetails, AddressDetails, ContactDetails and Success. The markup of BasicDetails view is shown below:

@model WizardInMVC.Models.BasicDetails

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>BasicDetails</title>
</head>
<body>
@using (Html.BeginForm("BasicDetails", "Home", FormMethod.Post))
{
<h1>Step 1 : Basic Details</h1>
@Html.LabelFor(m=>m.CustomerID)<br />
@Html.TextBoxFor(m=>m.CustomerID)
@Html.ValidationMessageFor(m=>m.CustomerID)<br />
@Html.LabelFor(m=>m.CompanyName)<br />
@Html.TextBoxFor(m=>m.CompanyName)
@Html.ValidationMessageFor(m=>m.CompanyName)
<br />
<input type="submit" name="nextBtn" value='Next' />
}
</body>
</html>

As you can see BasicDetails view has its model set to BasicDetails class. The view renders a form using BeginForm() Html helper that posts to BasicDetails() action method of HomeController. Form fields for CustomerID and CompanyName are rendered using LabelFor() and TextBoxFor() helpers. The validation errors are emitted using ValidationMessageFor() helper. Note that the name of the Next button must match the corresponding parameter name of the BasicDetails() action method (nextBtn in this case). The following figure shows the BasicDetails view in action:

image

The AddressDetails view is similar to BasicDetails but has Previous button also. The markup of AddressDetails view is shown below:

@model WizardInMVC.Models.AddressDetails

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>AddressDetails</title>
</head>
<body>
@using (Html.BeginForm("AddressDetails", "Home", FormMethod.Post))
{
<h1>Step 2 : Address Details</h1>
@Html.LabelFor(m=>m.Address)<br />
@Html.TextBoxFor(m=>m.Address)
@Html.ValidationMessageFor(m=>m.Address)
<br />
@Html.LabelFor(m=>m.City)<br />
@Html.TextBoxFor(m=>m.City)
@Html.ValidationMessageFor(m=>m.City)
<br />
@Html.LabelFor(m=>m.Country)<br />
@Html.TextBoxFor(m=>m.Country)
@Html.ValidationMessageFor(m=>m.Country)
<br />
@Html.LabelFor(m=>m.PostalCode)<br />
@Html.TextBoxFor(m=>m.PostalCode)
@Html.ValidationMessageFor(m=>m.PostalCode)
<br />
<input type="submit" name="prevBtn" value='Previous' />
<input type="submit" name="nextBtn" value='Next' />
}
</body>
</html>

AddressDetails view renders fields for Address, City, Country and PostalCode model properties. It also has prevBtn and nextBtn buttons that represent the Previous and Next button respectively. The AddressDetails view posts the form to AddressDetails() action method of HomeController. The following figure shows how AddressDetails view looks like along with validation errors.

image

The final wizard step - ContactDetails - consists of form fields for ContactName, Phone and Fax. It has two buttons Previous and Finish. The markup of ContactDetails view is shown below:

@model WizardInMVC.Models.ContactDetails

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>ContactDetails</title>
</head>
<body>
@using (Html.BeginForm("ContactDetails", "Home", FormMethod.Post))
{
<h1>Step 3 : Contact Details</h1>
@Html.LabelFor(m=>m.ContactName)<br />
@Html.TextBoxFor(m=>m.ContactName)
@Html.ValidationMessageFor(m=>m.ContactName)
<br />
@Html.LabelFor(m=>m.Phone)<br />
@Html.TextBoxFor(m=>m.Phone)
@Html.ValidationMessageFor(m=>m.Phone)
<br />
@Html.LabelFor(m=>m.Fax)<br />
@Html.TextBoxFor(m=>m.Fax)
@Html.ValidationMessageFor(m=>m.Fax)
<br />
<input type="submit" name="prevBtn" value='Previous' />
<input type="submit" name="nextBtn" value='Finish' />
}
</body>
</html>

As you can see the ContactDetails view posts to ContactDetails() action method of HomeController. Notice that this time nextBtn has a value of Finish since it is the last step of the wizard. The following figure shows ContactDetails in action:

image

Finally, you need to add the Success view that displays a success method and has a link to run the wizard again. The markup of success view is shown below:

@{
Layout = null;
}

<!DOCTYPE html>

<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Success</title>
</head>
<body>
<h3>Customer Data Saved Successfully!</h3>
@Html.ActionLink("Add Another Customer","Index","Home")
</body>
</html>

As you can see the ActionLink() helper renders an action link that points to the Index action method of HomeController. The following figure shows how the Success view looks like:

image

That's it! You can now run the wizard and test whether it works as expected. In the second part of this article you will learn to create a wizard using Ajax techniques.

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