TControl.Enabled
From OpenEUO
RW Enabled : b Controls whether the control responds to mouse, keyboard, and timer events.
Use Enabled to change the availability of the control to the user. To disable a control, set Enabled to false. Disabled controls appear dimmed. If Enabled is false, the control ignores mouse, keyboard, and timer events. To re-enable a control, set Enabled to true. The control is no longer dimmed, and the user can use the control.
