Model Binding Feature in Asp.Net 4.5

Model binding isn’t exactly a “new” feature when it comes to .NET because ASP.NET MVC has had it for a long time. However, it’s new to ASP.NET Web Forms and yet another feature that will truly change how you write your application code if you take advantage of what it offers.

Model binding is the process of getting model objects in and out of controls without writing a lot of plumbing code to do it. You can now bind data controls directly to methods that provide select, insert, update and delete functionality. When the methods are called you don’t have to write a lot of code to access the values that were posted back in the case of update, insert, or delete operations. Instead, model binding allows you to have a given model object’s properties (a class with properties if you’re not familiar with model objects) automatically filled with the posted back data.

Data bound controls are the major part of typical web form applications and we spend a lot of time in writing code related to different events of that control.

The new functionality makes task easier so that you as a developer can focus on data and entities. To better understand the code let me first explain the scenario.

We want to display all the records of above table in GridView control which  also supports Paging and Sorting functionality. How would we do this?

OLDER WAY

To display data in Gridview, we required markup like that:

<asp:GridView ID="gvCustomer" runat="server" AllowSorting="true"

OnSorting="gvCustomer_Sorting">

</asp:GridView>

To populate GridView from code-behind, we required code as:

var dataContext = new DatabaseDataContext(Classes.GetConnectionString);

var CustomerList = (from e in dataContext.Customers

                   select e).ToList();

if (CustomerList.Count > 0)

{

   gvCustomer.DataSource = CustomerList;

   gvCustomer.DataBind();

}

And we need to create separate events of GridView, in order to use Paging or Sotring like,

protected void gvCustomer_Sorting(object sender, GridViewSortEventArgs e)

{

    var dataContext = new DatabaseDataContext(Classes.GetConnectionString);

    var CustomerList = (from e in dataContext.Customers

                   select e).ToList();

    if (CustomerList.Count > 0)

    {

       gvCustomer.DataSource = CustomerList;

       gvCustomer.DataBind();

    }

}

NEW WAY

Asp.Net 4.5 introduce a new feature called Model Binding which take advantage of System.Linq.IQueryable type.

public IQueryable<Customer> GetCustomersList()

{

    var dataContext = new DatabaseDataContext(Classes.GetConnectionString);

    IQueryable<Customers> CustomerList = (from e in dataContext.Customers

                   select e).ToList();

    return CustomerList;

}

Now write a Gridview control markup as:

<asp:GridView ID="gvCustomer" runat="server"

    ItemType="DataBindingSample.Customers" SelectMethod="GetCustomers">

</asp;GridView>

Here:

·         ItemType refers to table name define within IQueryable tag

·         SelectMethod refers to name of method

Now run the application, it will show you all records from table "Customer" in GridView. If you want to add Paging or Sorting functionality, go ahead just allow both functionality in GridView markup and rest of things will be handle by Model Binding itself.

It would change the way how data controls were generally managed in web form applications.

Model binding allows model objects to be bound directly to controls and allows data that’s posted back to automatically be mapped into model object properties. It’s a feature I’ve wanted for quite awhile since I’ve used it heavily in ASP.NET MVC applications. By using the feature you can significantly enhance your productivity and minimize the amount of code you have to write.