Activating a form brings it to the front if this is the active application, or it flashes the window caption if this is not the active application. The form must be visible for this method to have any effect. To determine the active form in an application, use the Form.ActiveForm property or the Form.ActiveMdiChild property if your forms are in a Multiple-document interface (MDI) application.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Assembly Versions: 1.0.5000.0, 2.0.0.0