BindingExpression Class

Definition

Namespace:

System.Windows.Data

Assembly:

PresentationFramework.dll

Contains information about a single instance of a Binding.

public ref class BindingExpression sealed : System::Windows::Data::BindingExpressionBase, System::Windows::IWeakEventListener

public sealed class BindingExpression : System.Windows.Data.BindingExpressionBase, System.Windows.IWeakEventListener

type BindingExpression = class
    inherit BindingExpressionBase
    interface IWeakEventListener

Public NotInheritable Class BindingExpression
Inherits BindingExpressionBase
Implements IWeakEventListener

Inheritance

Object

Expression

BindingExpressionBase

BindingExpression

Implements

IWeakEventListener

Remarks

The Binding class is the high-level class for the declaration of a binding. The BindingExpression class is the underlying object that maintains the connection between the binding source and the binding target. A Binding contains all the information that can be shared across several BindingExpression objects. A BindingExpression is an instance expression that cannot be shared and that contains all the instance information about the Binding.

For example, consider the following, where myDataObject is an instance of the MyData class, myBinding is the source Binding object, and MyData class is a defined class that contains a string property named MyDataProperty. This example binds the text content of mytext, which is an instance of TextBlock, to MyDataProperty.

// Make a new source.
MyData myDataObject = new MyData(DateTime.Now);      
Binding myBinding = new Binding("MyDataProperty");
myBinding.Source = myDataObject;
// Bind the new data source to the myText TextBlock control's Text dependency property.
myText.SetBinding(TextBlock.TextProperty, myBinding);

' Make a new source.
Dim data1 As New MyData(DateTime.Now)
Dim binding1 As New Binding("MyDataProperty")
binding1.Source = data1
' Bind the new data source to the myText TextBlock control's Text dependency property.
Me.myText.SetBinding(TextBlock.TextProperty, binding1)

You can use the same myBinding object to create other bindings. For example, you might use the myBinding object to bind the text content of a check box to MyDataProperty. In that scenario, there will be two instances of BindingExpression that share the myBinding object.

You can obtain a BindingExpression object by using the GetBindingExpression method or the GetBindingExpression method on a data-bound object.

Properties

BindingGroup	Gets the BindingGroup that this binding expression belongs to. (Inherited from BindingExpressionBase)
DataItem	Gets the binding source object that this BindingExpression uses.
HasError	Gets a value that indicates whether the parent binding has a failed validation rule. (Inherited from BindingExpressionBase)
HasValidationError	Gets a value that indicates whether the parent binding has a failed validation rule. (Inherited from BindingExpressionBase)
IsDirty	Gets or sets a value that indicates whether the target of the binding has a value that has not been written to the source. (Inherited from BindingExpressionBase)
ParentBinding	Returns the Binding object of the current BindingExpression.
ParentBindingBase	Gets the BindingBase object from which this BindingExpressionBase object is created. (Inherited from BindingExpressionBase)
ResolvedSource	Gets the binding source object for this BindingExpression.
ResolvedSourcePropertyName	Gets the name of the binding source property for this BindingExpression.
Status	Gets the status of the binding expression. (Inherited from BindingExpressionBase)
Target	Gets the element that is the binding target object of this binding expression. (Inherited from BindingExpressionBase)
TargetProperty	Gets the binding target property of this binding expression. (Inherited from BindingExpressionBase)
ValidationError	Gets the ValidationError that caused this instance of BindingExpressionBase to be invalid. (Inherited from BindingExpressionBase)
ValidationErrors	Gets a collection of ValidationError objects that caused this instance of BindingExpressionBase to be invalid. (Inherited from BindingExpressionBase)

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)
UpdateSource()	Sends the current binding target value to the binding source property in TwoWay or OneWayToSource bindings.
UpdateTarget()	Forces a data transfer from the binding source property to the binding target property.
ValidateWithoutUpdate()	Runs any ValidationRule objects on the associated Binding that have the ValidationStep property set to RawProposedValue or ConvertedProposedValue. This method does not update the source. (Inherited from BindingExpressionBase)

Explicit Interface Implementations

IWeakEventListener.ReceiveWeakEvent(Type, Object, EventArgs)

This member supports the Windows Presentation Foundation (WPF) infrastructure and is not intended to be used directly from your code.