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LinqDataSource.Deleting Event

Definition

Occurs before a delete operation.

public:
 event EventHandler<System::Web::UI::WebControls::LinqDataSourceDeleteEventArgs ^> ^ Deleting;
public event EventHandler<System.Web.UI.WebControls.LinqDataSourceDeleteEventArgs> Deleting;
member this.Deleting : EventHandler<System.Web.UI.WebControls.LinqDataSourceDeleteEventArgs> 
Public Custom Event Deleting As EventHandler(Of LinqDataSourceDeleteEventArgs) 

Event Type

Examples

The following example shows an event handler for the Deleting event. The code cancels the delete operation based on a property in the OriginalObject property and a value from the Web page. In the example, when the OnSale property is set to true, the user must select a CheckBox control to confirm that a record should be deleted.

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

Handle the Deleting event to validate the object to be deleted, to examine data validation errors from the data class, to change a value before the delete operation, or to cancel the delete operation. The LinqDataSource control passes a LinqDataSourceDeleteEventArgs object to event handlers for the Deleting event. The LinqDataSourceDeleteEventArgs object contains the data that will be deleted and enables you to cancel the delete operation. If the data class throws a LinqDataSourceValidationException exception, the LinqDataSourceDeleteEventArgs object contains that exception in the Exception property.

If an exception is thrown in an event handler for the Deleting event, you must handle the exception in that event handler. The exception will not be passed to an event handler for the Deleted event (through the Exception property of the LinqDataSourceStatusEventArgs object). The Exception property contains only the exceptions that are thrown after the Deleting event.

Applies to