项目
11/17/2011

DataServiceCollection<T> Constructor (DataServiceContext, IEnumerable<T>, TrackingMode, String, Func<EntityChangedParams, Boolean>, Func<EntityCollectionChangedParams, Boolean>)

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Creates a new instance of the DataServiceCollection<T> class a based on query execution, with the supplied change method delegates, and that uses the supplied DataServiceContext.

Namespace: System.Data.Services.Client
Assembly: System.Data.Services.Client (in System.Data.Services.Client.dll)

Syntax

'Declaration
Public Sub New ( _
    context As DataServiceContext, _
    items As IEnumerable(Of T), _
    trackingMode As TrackingMode, _
    entitySetName As String, _
    entityChangedCallback As Func(Of EntityChangedParams, Boolean), _
    collectionChangedCallback As Func(Of EntityCollectionChangedParams, Boolean) _
)

public DataServiceCollection(
    DataServiceContext context,
    IEnumerable<T> items,
    TrackingMode trackingMode,
    string entitySetName,
    Func<EntityChangedParams, bool> entityChangedCallback,
    Func<EntityCollectionChangedParams, bool> collectionChangedCallback
)

Parameters

context
Type: System.Data.Services.Client.DataServiceContext
The DataServiceContext used to track items in the collection.

items
Type: System.Collections.Generic.IEnumerable<T>
A DataServiceQuery<TElement> or LINQ query that returns an IEnumerable<T> collection of objects that are used to initialize the collection.

trackingMode
Type: System.Data.Services.Client.TrackingMode
A TrackingMode value that indicated whether or not changes made to items in the collection are automatically tracked.

entitySetName
Type: System.String
The entity set of the objects in the collection.

entityChangedCallback
Type: System.Func<EntityChangedParams, Boolean>
A delegate that encapsulates a method that is called when an entity changes.

collectionChangedCallback
Type: System.Func<EntityCollectionChangedParams, Boolean>
A delegate that encapsulates a method that is called when the collection of entities changes.

Remarks

By default, automatic change tracking is enabled for a DataServiceCollection<T>. Use this class constructor and supply a value of None for trackingMode to create an instance of DataServiceCollection<T> that uses manual change tracking. When you use manual tracking, you must implement INotifyPropertyChanged and INotifyCollectionChanged and handle the raised events to manually report changes to the DataServiceContext.

The DataServiceContext must be supplied when items is not a DataServiceQuery<TElement> or QueryOperationResponse<T> that has a reference to a DataServiceContext instance.

The entityChanged and collectionChanged functions are invoked by the PropertyChanged and CollectionChanged events, respectively. The entityChanged method takes an EntityCollectionChangedParams value and the collectionChanged method takes a EntityChangedParams value. Both methods must return a Boolean value that indicates whether the event was handled by the function. When the method returns true, the default behavior will still occur.

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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