The CheckBox.OnClick(EventArgs) method changes the CheckBox.CheckState property. If the CheckBox.ThreeState property is set to true, subsequent clicks of the System.Windows.Forms.CheckBox will result in CheckBox.OnClick(EventArgs) cycling through all the values of the CheckBox.CheckState enumeration. Otherwise, CheckBox.OnClick(EventArgs) switches between CheckState.Checked and CheckState.Unchecked.

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The CheckBox.OnClick(EventArgs) method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

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