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GroupDescriptor Class

WCF RIA Services

[WCF RIA Services Version 1 Service Pack 2 is compatible with either .NET framework 4 or .NET Framework 4.5, and with either Silverlight 4 or Silverlight 5.]

Describes a grouping criterion.

System.Object
  System.Windows.DependencyObject
    System.Windows.Controls.GroupDescriptor

Namespace:  System.Windows.Controls
Assembly:  System.Windows.Controls.DomainServices (in System.Windows.Controls.DomainServices.dll)
C#
C++
F#
JScript
VB
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public class GroupDescriptor : DependencyObject

The GroupDescriptor type exposes the following members.

  Name Description
Public method GroupDescriptor() Initializes a new instance of the GroupDescriptor class with default values.
Public method GroupDescriptor(String) Initializes a new instance of the GroupDescriptor class with the specified property path.
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  Name Description
Public property Dispatcher (Inherited from DependencyObject.)
Public property PropertyPath Gets or sets the public property used to group.
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  Name Description
Public method CheckAccess (Inherited from DependencyObject.)
Public method ClearValue (Inherited from DependencyObject.)
Public method Equals (Inherited from Object.)
Protected method Finalize (Inherited from Object.)
Public method GetAnimationBaseValue (Inherited from DependencyObject.)
Public method GetHashCode (Inherited from Object.)
Public method GetType (Inherited from Object.)
Public method GetValue (Inherited from DependencyObject.)
Protected method MemberwiseClone (Inherited from Object.)
Public method ReadLocalValue (Inherited from DependencyObject.)
Public method SetValue (Inherited from DependencyObject.)
Public method ToString (Inherited from Object.)
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  Name Description
Public field Static member PropertyPathProperty Identifies the PropertyPath dependency property.
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The DomainDataSource class provides the GroupDescriptors collection to facilitate grouping data by property values. In the GroupDescriptors collection, you add GroupDescriptor instances that define the value to use for grouping. You can add as many GroupDescriptor instances as needed.

If you use GroupDescriptor programmatically, verify that the CanLoad property returns true. Attempting to group when CanLoad returns false, causes the DomainDataSource to throw an invalid operation exception. Grouping initiates a load operation, and load operations are not permitted when CanLoad is false.

The following example shows how to add a value to use for grouping.

XAML
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<Grid x:Name="LayoutRoot" Background="White">  
    <riaControls:DomainDataSource x:Name="source" QueryName="GetProducts" AutoLoad="true">
        <riaControls:DomainDataSource.DomainContext>
            <domain:ProductDomainContext />
        </riaControls:DomainDataSource.DomainContext>   
        <riaControls:DomainDataSource.GroupDescriptors>
            <riaData:GroupDescriptor PropertyPath="Size" />
        </riaControls:DomainDataSource.GroupDescriptors>
    </riaControls:DomainDataSource>
    <data:DataGrid ItemsSource="{Binding Data, ElementName=source}" />
</Grid>
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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