In order for a control to receive input focus, the control must have a handle assigned to it, and the Visible and Enabled properties must both be set to true for both the control and all its parent controls, and the control must be a form or the control's outermost parent must be a form.
public:
void ControlSetFocus( Control^ control )
{
// Set focus to the control, if it can receive focus.if ( control->CanFocus )
{
control->Focus();
}
}