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LinqDataSourceContextEventArgs Class

Provides data for the ContextCreating event.


Namespace:  System.Web.UI.WebControls
Assembly:  System.Web.Extensions (in System.Web.Extensions.dll)

Public Class LinqDataSourceContextEventArgs _
	Inherits EventArgs

The LinqDataSourceContextEventArgs type exposes the following members.

Public methodLinqDataSourceContextEventArgsInitializes a new instance of the LinqDataSourceContextEventArgs class.
Public methodLinqDataSourceContextEventArgs(DataSourceOperation)Initializes a new instance of the LinqDataSourceContextEventArgs class for the specified data operation.

Public propertyObjectInstanceGets or sets the data context object to create.
Public propertyOperationGets the data operation that is being performed.

Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

By default, the LinqDataSource control creates an instance of the type that is specified in the ContextTypeName property. The LinqDataSource control calls the default constructor of the data context object to create an instance of the object.

You can manually create the data context object by handling the ContextCreating event. You do this if you want to use a non-default constructor.

You can also handle the ContextCreating event if you want to create a data context object that is different from the one specified in the ContextTypeName property. In that case, you set the ObjectInstance property to the object you created. The LinqDataSource control will use the object you have created for selecting the data. When you are updating, inserting, or deleting data, you must set the ObjectInstance property to an object that derives from the DataContext class.

The following example shows how to create the data context object by calling a non-default constructor in an event handler for the ContextCreating event. The code assigns the custom object to the ObjectInstance property.

Protected Sub LinqDataSource_ContextCreating(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.LinqDataSourceContextEventArgs)
    e.ObjectInstance = New ExampleDataContext(ConfigurationManager.ConnectionStrings("ExampleConnectionString").ConnectionString)
End Sub

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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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