Provides high-level access to the definition of a binding, which connects the properties of binding target objects (typically, WPF elements), and any data source (for example, a database, an XML file, or any object that contains data).
Assembly: PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
Thetype exposes the following members.
|AsyncState||Infrastructure. Gets or sets opaque data passed to the asynchronous data dispatcher.|
|BindingGroupName||Gets or sets the name of the BindingGroup to which this binding belongs. (Inherited from BindingBase.)|
|BindsDirectlyToSource||Gets or sets a value that indicates whether to evaluate the Path relative to the data item or the DataSourceProvider object.|
|Converter||Gets or sets the converter to use.|
|ConverterCulture||Gets or sets the culture in which to evaluate the converter.|
|ConverterParameter||Gets or sets the parameter to pass to the Converter.|
|Delay||Gets or sets the amount of time, in milliseconds, to wait before updating the binding source after the value on the target changes. (Inherited from BindingBase.)|
|ElementName||Gets or sets the name of the element to use as the binding source object.|
|FallbackValue||Gets or sets the value to use when the binding is unable to return a value. (Inherited from BindingBase.)|
|IsAsync||Gets or sets a value that indicates whether the should get and set values asynchronously.|
|Mode||Gets or sets a value that indicates the direction of the data flow in the binding.|
|NotifyOnSourceUpdated||Gets or sets a value that indicates whether to raise the SourceUpdated event when a value is transferred from the binding target to the binding source.|
|NotifyOnTargetUpdated||Gets or sets a value that indicates whether to raise the TargetUpdated event when a value is transferred from the binding source to the binding target.|
|NotifyOnValidationError||Gets or sets a value that indicates whether to raise the Error attached event on the bound object.|
|Path||Gets or sets the path to the binding source property.|
|RelativeSource||Gets or sets the binding source by specifying its location relative to the position of the binding target.|
|Source||Gets or sets the object to use as the binding source.|
|StringFormat||Gets or sets a string that specifies how to format the binding if it displays the bound value as a string. (Inherited from BindingBase.)|
|TargetNullValue||Gets or sets the value that is used in the target when the value of the source is null. (Inherited from BindingBase.)|
|UpdateSourceExceptionFilter||Gets or sets a handler you can use to provide custom logic for handling exceptions that the binding engine encounters during the update of the binding source value. This is only applicable if you have associated an ExceptionValidationRule with your binding.|
|UpdateSourceTrigger||Gets or sets a value that determines the timing of binding source updates.|
|ValidatesOnDataErrors||Gets or sets a value that indicates whether to include the DataErrorValidationRule.|
|ValidatesOnExceptions||Gets or sets a value that indicates whether to include the ExceptionValidationRule.|
|ValidatesOnNotifyDataErrors||Gets or sets a value that indicates whether to include the NotifyDataErrorValidationRule.|
|ValidationRules||Gets a collection of rules that check the validity of the user input.|
|XPath||Gets or sets an XPath query that returns the value on the XML binding source to use.|
|AddSourceUpdatedHandler||Adds a handler for the SourceUpdated attached event.|
|AddTargetUpdatedHandler||Adds a handler for the TargetUpdated attached event.|
|Equals(Object)||Determines whether the specified object is equal to the current object. (Inherited from Object.)|
|Finalize||Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)|
|GetHashCode||Serves as the default hash function. (Inherited from Object.)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|GetXmlNamespaceManager||Returns an XML namespace manager object used by the binding attached to the specified object.|
|MemberwiseClone||Creates a shallow copy of the current Object. (Inherited from Object.)|
|ProvideValue||Returns an object that should be set on the property where this binding and extension are applied. (Inherited from BindingBase.)|
|RemoveSourceUpdatedHandler||Removes a handler for the SourceUpdated attached event.|
|RemoveTargetUpdatedHandler||Removes a handler for the TargetUpdated attached event.|
|SetXmlNamespaceManager||Sets a namespace manager object used by the binding attached to the provided element.|
|ShouldSerializeFallbackValue||Returns a value that indicates whether serialization processes should serialize the effective value of the FallbackValue property on instances of this class. (Inherited from BindingBase.)|
|ShouldSerializePath||Indicates whether the Path property should be persisted.|
|ShouldSerializeSource||Indicates whether the Source property should be persisted.|
|ShouldSerializeTargetNullValue||Returns a value that indicates whether the TargetNullValue property should be serialized. (Inherited from BindingBase.)|
|ShouldSerializeValidationRules||Indicates whether the ValidationRules property should be persisted.|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
|SourceUpdated||Occurs when a value is transferred from the binding target to the binding source, but only for bindings with the NotifyOnSourceUpdated value set to true.|
|TargetUpdated||Occurs when a value is transferred from the binding source to the binding target, but only for bindings with the NotifyOnTargetUpdated value set to true.|
|DoNothing||Used as a returned value to instruct the binding engine not to perform any action.|
|IndexerName||Used as the PropertyName of System.ComponentModel.PropertyChangedEventArgs to indicate that an indexer property has changed.|
|SourceUpdatedEvent||Identifies the SourceUpdated attached event.|
|TargetUpdatedEvent||Identifies the TargetUpdated attached event.|
|XmlNamespaceManagerProperty||Identifies the XmlNamespaceManager attached property.|
Windows Presentation Foundation (WPF) data binding provides a simple and consistent way for applications to present and interact with data. Data binding enables you to synchronize the values of the properties of two different objects.
To establish a binding, use the class or one of the other classes that inherit BindingBase. Regardless of what object you are binding and the nature of your data source, each binding follows the model illustrated by the following figure.
The figure demonstrates the following fundamental WPF data binding concepts.
Each binding typically has these four components: a binding target object, a target property, a binding source, and a Path to the value in the binding source to use. For example, if you want to bind the content of a TextBox to the Name property of an Employee object, your target object is the TextBox, the target property is the Text property, the value to use is Name, and the source object is the Employee object.
The target property must be a dependency property. This also means that you cannot bind a field. Most properties of UIElement objects are dependency properties and most dependency properties, except read-only ones, support data binding by default. (Only DependencyObject types can define dependency properties and all UIElement objects derive from DependencyObject.)
Although not specified in the figure, it should be noted that the binding source object is not restricted to being a custom CLR object. WPF data binding supports data in the form of CLR objects and XML. To provide some examples, your binding source may be a UIElement, any list object, a CLR object that is associated with ADO.NET data or Web Services, or an XmlNode that contains your XML data.
Use the Mode property to specify the direction of the data flow. To detect source changes in one-way or two-way bindings, the source must implement a suitable property change notification mechanism such as INotifyPropertyChanged. For an example, see How to: Implement Property Change Notification. The UpdateSourceTrigger property specifies the timing of source updates. For more information, see "Basic Data Binding Concepts" in Data Binding Overview.
This example shows you how to create a simple .
In this example, you have a Person object with a string property named PersonName. The Person object is defined in the namespace called SDKSample.
The following example instantiates the Person object with a PersonName property value of Joe. This is done in the Resources section and assigned an x:Key.
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:src="clr-namespace:SDKSample" SizeToContent="WidthAndHeight" Title="Simple Data Binding Sample"> <Window.Resources> <src:Person x:Key="myDataSource" PersonName="Joe"/> ... </Window.Resources> ... </Window>
To bind to the PersonName property you would do the following:
As a result, the TextBlock appears with the value "Joe".
|How to: Specify the Binding Source||In data binding, the binding source object refers to the object you obtain your data from. This topic describes the different ways of specifying the binding source.|
|How to: Create a Binding in Code||This example shows how to create and set a in code.|
|How to: Bind to XML Data Using an XMLDataProvider and XPath Queries||This example shows how to bind to XML data using an XmlDataProvider.|
|How to: Implement Property Change Notification||To support OneWay or TwoWay binding to enable your binding target properties to automatically reflect the dynamic changes of the binding source (for example, to have the preview pane updated automatically when the user edits a form), your class needs to provide the proper property changed notifications. This example shows how to create a class that implements INotifyPropertyChanged.|
|How to: Specify the Direction of the Binding||This example shows how to specify whether the binding updates only the binding target (target) property, the binding source (source) property, or both the target property and the source property.|
|How to: Control When the TextBox Text Updates the Source||This topic describes how to use the UpdateSourceTrigger property to control the timing of binding source updates. The topic uses the TextBox control as an example.|
|How to: Bind to an ADO.NET Data Source||This example shows how to bind a Windows Presentation Foundation (WPF) ListBox control to an ADO.NET DataSet.|
|How to: Sort Data in a View||This example describes how to sort data in a view.|
|How to: Filter Data in a View||This example shows how to filter data in a view.|
|How to: Bind to an Enumeration||This example shows how to bind to an enumeration by binding to the enumeration's GetValues method.|