FrameworkElement.GetBindingExpression Method
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Retrieves the BindingExpression for a dependency property where a binding is established.
Namespace: System.Windows
Assembly: System.Windows (in System.Windows.dll)
Syntax
'Declaration
Public Function GetBindingExpression ( _
dp As DependencyProperty _
) As BindingExpression
public BindingExpression GetBindingExpression(
DependencyProperty dp
)
Parameters
- dp
Type: System.Windows.DependencyProperty
The dependency property identifier for the specific property on this FrameworkElement where you want to obtain the BindingExpression.
Return Value
Type: System.Windows.Data.BindingExpression
A BindingExpression for the binding, if the local value represented a data-bound value. May return nulla null reference (Nothing in Visual Basic) if the property is not a data-bound value.
Remarks
In the current implementation, this method returns the same result as ReadLocalValue, with the return value cast to BindingExpression.
You could potentially use GetBindingExpression as a test to see whether a given dependency property has a binding applied to it, by attempting the cast of the return value to BindingExpression. If this succeeds, the property is currently being set by a data-bound value. If the value is nulla null reference (Nothing in Visual Basic) rather than a BindingExpression, then the property you queried is not data-bound.
A BindingExpression object enables the following scenarios with its API:
You can force a source update for a binding independent of the existing update trigger on the binding by calling BindingExpression.UpdateSource.
You can access the current source value by calling BindingExpression.DataItem.
You can obtain more information about the original binding and its declaration by calling BindingExpression.ParentBinding. From the returned object, you can determine Binding.Mode, Binding.Path, and so on.
For more information, see BindingExpression or Data Binding.
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.
See Also