Silverlight 4 Custom Property Binding

A common scenario you might encounter is wanting to create a bindable property on a custom control. The way we do this is using a static DependencyProperty member as our backing field. Below is an example of a CustomTextBox with a string CustomString property:

using System.Windows; 

public class CustomTextBox : System.Windows.Controls.TextBox 

{

    public static readonly DependencyProperty CustomStringProperty = DependencyProperty.Register

        (

            "CustomString",

            typeof(bool),

            typeof(CustomTextBox),

            null 

        );

    public string CustomString

    {

        get { return (string)GetValue(CustomStringProperty); }

        set { SetValue(CustomStringProperty, value); }

    } 

}

You can now use the CustomTextBox in your XAML, and bind directly to the CustomString property.

Just a simple example to illustrate how its done. If you want more information on how it all works, check out the MSDN documentation.