BindingExpression Class

Definition

Contains information about a single instance of a Binding.

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

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;
  myText.SetBinding(TextBlock.TextProperty, myBinding);
Dim data1 As New MyData(DateTime.Now)
Dim binding1 As New Binding("MyDataProperty")
binding1.Source = data1
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.

Applies to