InvalidateEventArgs Class

The Invalidated event occurs when a control's display is updated. An InvalidateEventArgs specifies the rectangle that contains the invalidated window area.

For information about the event model, see Events and Delegates.

The following code example demonstrates the use of this type. In the example, an event handler reports on the occurrence of the Invalidated event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing Show with Console.WriteLine or appending the message to a multiline TextBox.

To run the example code, paste it into a project that contains an instance of a type that inherits from Control, such as a Button or ComboBox. Then name the instance Control1 and ensure that the event handler is associated with the Invalidated event.

private void Control1_Invalidated(Object sender, InvalidateEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "InvalidRect", e.InvalidRect );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "Invalidated Event" );
}

.NET Framework

.NET Framework Client Profile

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference