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FrameworkElement.GetBindingExpression 方法

Returns the BindingExpression that represents the binding on the specified property.

命名空间: System.Windows
程序集: PresentationFramework(在 presentationframework.dll 中)

public BindingExpression GetBindingExpression (
	DependencyProperty dp
)
public BindingExpression GetBindingExpression (
	DependencyProperty dp
)
public function GetBindingExpression (
	dp : DependencyProperty
) : BindingExpression
不能在 XAML 中使用方法。

参数

dp

The target DependencyProperty to get the binding from.

返回值

A BindingExpression if the target property has an active binding; otherwise, returns 空引用(在 Visual Basic 中为 Nothing).

Checking the return value for 空引用(在 Visual Basic 中为 Nothing) is a technique you can use to determine whether a property has an active binding.

This method is really just a convenience wrapper around the BindingOperations.GetBindingExpression method. GetBindingExpression passes the current instance and the dp parameter to BindingOperations.GetBindingExpression.

This example shows how to obtain the binding object from a data-bound target property.

You can do the following to get the Binding object:

// textBox3 is an instance of a TextBox
// the TextProperty is the data-bound dependency property
Binding myBinding = BindingOperations.GetBinding(textBox3, TextBox.TextProperty);

说明注意:

You must specify the dependency property for the binding you want because it is possible that more than one property of the target object is using data binding.

Alternatively, you can get the BindingExpression and then get the value of the ParentBinding property.

For the complete example see Binding Validation Sample.

说明注意:

If your binding is a MultiBinding, use BindingOperations.GetMultiBinding. If it is a PriorityBinding, use BindingOperations.GetPriorityBinding. If you are uncertain whether the target property is bound using a Binding, a MultiBinding, or a PriorityBinding, you can use BindingOperations.GetBindingBase.

Windows Vista、Microsoft Windows XP SP2 和 Windows Server 2003 SP1 支持 Microsoft .NET Framework 3.0。

.NET Framework

受以下版本支持:3.0

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