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LinqDataSourceDeleteEventArgs Class

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.Extensions.dll

Provides data for the Deleting event.

public ref class LinqDataSourceDeleteEventArgs : System::ComponentModel::CancelEventArgs
public class LinqDataSourceDeleteEventArgs : System.ComponentModel.CancelEventArgs
type LinqDataSourceDeleteEventArgs = class
    inherit CancelEventArgs
Public Class LinqDataSourceDeleteEventArgs
Inherits CancelEventArgs
Inheritance
Object
EventArgs
CancelEventArgs
LinqDataSourceDeleteEventArgs

Examples

The following example shows how to cancel the delete operation based on a property in the OriginalObject property and a value from the Web page. In the example, users must select a CheckBox control to confirm that they want to delete a product record when its OnSale property is set to true.

protected void LinqDataSource_Deleting(object sender, LinqDataSourceDeleteEventArgs e)
{
    Product product = (Product)e.OriginalObject;
    if (product.OnSale && !confirmCheckBox.Checked)
    {
        e.Cancel = true;
    }
}

Protected Sub LinqDataSource_Deleting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.LinqDataSourceDeleteEventArgs)
    Dim product As Product
    product = CType(e.OriginalObject, Product)

    If (product.OnSale And Not confirmCheckBox.Checked) Then
        e.Cancel = True
    End If
End Sub

Remarks

The LinqDataSourceDeleteEventArgs object is passed to any handler for the Deleting event. The OriginalObject property contains the data that will be deleted.

If the object that represents the data source throws a validation exception before it deletes the data, the Exception property contains an instance of the LinqDataSourceValidationException class. You can retrieve all the validation exceptions through the InnerExceptions property. If no validation exception is thrown, the Exception property contains null. If you handle the validation exceptions and do not want the exception to be re-thrown, set the ExceptionHandled property to true.

You create an event handler for the Deleting event to validate the data, to examine validation errors from the data class, or to cancel the delete operation. You cancel the delete operation by setting the Cancel property to true.

By default, the LinqDataSource control stores the original values from the data source in view state in the Web page, except those whose ColumnAttribute attribute is marked as UpdateCheck.Never. LINQ to SQL automatically checks the integrity of the data before deleting the data. It does this by comparing the current values in the data source with the original values that are stored in view state. You can perform additional data validation by creating a handler for the Deleting event.

Constructors

LinqDataSourceDeleteEventArgs(LinqDataSourceValidationException)

Initializes a new instance of the LinqDataSourceDeleteEventArgs class with the specified exception.
LinqDataSourceDeleteEventArgs(Object)

Initializes a new instance of the LinqDataSourceDeleteEventArgs class.

Properties

Cancel

Gets or sets a value indicating whether the event should be canceled.

(Inherited from CancelEventArgs)
Exception

Gets the exception that was thrown while the data was being validated before the delete operation.
ExceptionHandled

Gets or sets a value that indicates whether the exception was handled and that it should not be thrown again.
OriginalObject

Gets the object that represents the data to delete.

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

See also