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LinqDataSourceContextEventArgs Class

Definition

Provides data for the ContextCreating event.

public ref class LinqDataSourceContextEventArgs : EventArgs
public class LinqDataSourceContextEventArgs : EventArgs
type LinqDataSourceContextEventArgs = class
    inherit EventArgs
Public Class LinqDataSourceContextEventArgs
Inherits EventArgs
Inheritance
LinqDataSourceContextEventArgs

Examples

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

protected void LinqDataSource_ContextCreating(object sender, LinqDataSourceContextEventArgs e)
{
    e.ObjectInstance = new ExampleDataContext(ConfigurationManager.ConnectionStrings["ExampleConnectionString"].ConnectionString);
}
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

Remarks

By default, the LinqDataSource control creates an instance of the type that is specified in the ContextTypeName property. The LinqDataSource control calls the parameterless 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-parameterless 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.

Constructors

LinqDataSourceContextEventArgs()

Initializes a new instance of the LinqDataSourceContextEventArgs class.

LinqDataSourceContextEventArgs(DataSourceOperation)

Initializes a new instance of the LinqDataSourceContextEventArgs class for the specified data operation.

Properties

ObjectInstance

Gets or sets the data context object to create.

Operation

Gets the data operation that is being performed.

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)

Applies to