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Binding to WCF Service

Updated on Sep 23, 2026

The purpose of this tutorial is to show you how to populate a RadComboBox with a data from a WCF Service in two ways:

Using plain methods call in the code-behind
Using MVVM approach

This tutorial uses the Northwind database.

Before proceeding further with this tutorial, you need to create a new application and a RadComboBox declaration in your XAML.

XAML

<telerik:RadComboBox />

Using Plain Methods Call in the Code-Behind

Add a reference to your WCF Service.

Switch to the code-behind and create a new instance of your WCF Service client.

ComboBoxWcfServiceClient serviceClient = new ComboBoxWcfServiceClient();

VB.NET

Dim serviceClient As New ComboBoxWcfServiceClient()

The ComboBox control will be populated with all Products from the Northwind database. In the drop-down list the ProductName and the UnitPrice properties will be displayed. Add the following code which will make the initial load of the objects.

private void BeginRequest()
{
	serviceClient.GetProductsCompleted += new EventHandler<GetProductsCompletedEventArgs>( serviceClient_GetProductsCompleted );
	serviceClient.GetProductsAsync();
}
private void serviceClient_GetProductsCompleted( object sender, GetProductsCompletedEventArgs e )
{
	radComboBox.ItemsSource = e.Result;
}

VB.NET

Private Sub BeginRequest()
	AddHandler serviceClient.GetProductsCompleted, AddressOf serviceClient_GetProductsCompleted
	serviceClient.GetProductsAsync()
End Sub
Private Sub serviceClient_GetProductsCompleted(ByVal sender As Object, ByVal e As GetProductsCompletedEventArgs)
	radComboBox.ItemsSource = e.Result
End Sub

private void BeginRequest()
{
    this.radComboBox.ItemsSource = serviceClient.GetProducts();
}

VB.NET

Private Sub BeginRequest()
	Me.radComboBox.ItemsSource = serviceClient.GetProducts()
End Sub

You need to declare a custom DataTemplate to determine how the items in the drop-down will look like. Add the following DataTemplate declaration in your XAML resources.

XAML

<UserControl.Resources>
    <DataTemplate x:Key="CustomItemTemplate">
        <StackPanel Orientation="Horizontal">
            <TextBlock Text="{Binding ProductName}"/>
            <TextBlock Text=" - "/>
            <TextBlock Text="{Binding UnitPrice}"/>
            <TextBlock Text=" $"/>
        </StackPanel>
    </DataTemplate>
</UserControl.Resources>

Find your RadComboBox declaration and set the declared DataTemplate to its ItemTemplate property.
XAML
```
<telerik:RadComboBox ItemTemplate="{StaticResource CustomItemTemplate}"/>
```

The end result with the data fetched from the service

WPF RadComboBox Bound to Data from WCF Service

Using MVVM Approach

This section will show you how to populate your RadComboBox control in a MVVM manner. The RadComboBox will be bound to a data source object, that has a property Products. When the control is loaded, all products from the Products table in the Northwind database are loaded asynchronously.

Create a new class named NorthwindDataSource.

private void serviceClient_GetProductsCompleted(object sender, GetProductsCompletedEventArgs e)
{
    foreach (Products p in e.Result)
    {
        this.Products.Add(p);
    }
}

VB.NET

For Each p As Products In serviceClient.GetProducts()
	Me.Products.Add(p)
Next

Add a reference to your WCF Service
In the NorthwindDataSource class add a reference to an ObservableCollection of Products.

In the NorthwindDataSource class add a reference to your WCF Service client:

private void serviceClient_GetProductsCompleted(object sender, GetProductsCompletedEventArgs e)
{
    foreach (Products p in e.Result)
    {
        this.Products.Add(p);
    }
}

VB.NET

For Each p As Products In serviceClient.GetProducts()
	Me.Products.Add(p)
Next

For more information about how to add a reference to a WCF Service and how to create a new instance of a WCF Service client, take a look at the Consuming WCF Service topic.

Add the following code in the constructor of the NorthwindDataSource. It will make the initial load of all Products from the database:

private void serviceClient_GetProductsCompleted(object sender, GetProductsCompletedEventArgs e)
{
    foreach (Products p in e.Result)
    {
        this.Products.Add(p);
    }
}

VB.NET

For Each p As Products In serviceClient.GetProducts()
	Me.Products.Add(p)
Next

private void serviceClient_GetProductsCompleted(object sender, GetProductsCompletedEventArgs e)
{
    foreach (Products p in e.Result)
    {
        this.Products.Add(p);
    }
}

VB.NET

For Each p As Products In serviceClient.GetProducts()
	Me.Products.Add(p)
Next

private void serviceClient_GetProductsCompleted(object sender, GetProductsCompletedEventArgs e)
{
    foreach (Products p in e.Result)
    {
        this.Products.Add(p);
    }
}

VB.NET

For Each p As Products In serviceClient.GetProducts()
	Me.Products.Add(p)
Next

Declare the NorthwindDataSource object as a resource in your application.

XAML

<telerik:RadComboBox x:Name="radComboBox"
	ItemsSource="{Binding Source={StaticResource DataSource}, Path=Products}"
	ItemTemplate="{StaticResource CustomItemTemplate}"/>

Declare a custom DataTemplate to determine how the items in the drop-down will look like. Add the following DataTemplate declaration in your XAML resources.

XAML

<telerik:RadComboBox x:Name="radComboBox"
	ItemsSource="{Binding Source={StaticResource DataSource}, Path=Products}"
	ItemTemplate="{StaticResource CustomItemTemplate}"/>

Update your RadComboBox declaration - set the ItemsSource and ItemTemplate properties.

XAML

<telerik:RadComboBox x:Name="radComboBox"
	ItemsSource="{Binding Source={StaticResource DataSource}, Path=Products}"
	ItemTemplate="{StaticResource CustomItemTemplate}"/>

The end result produced by the code above

WPF RadComboBox Bound to Data from WCF Service

Binding to WCF Service

Using Plain Methods Call in the Code-Behind

Using MVVM Approach

See Also