How do I know if a Form is hovering over a component?

Question

I need to know if a (moving) form is hovering over a component (maybe something like MouseEnter and MouseLeave without the mouse).

I have this idea of getting the Left, Top, Height, Width of the component and calculating if the (moving) form's position is within the position of the form. (I'm not exactly sure how I can do this)

Any suggestions on implementing my idea? Is there any other way I can do this?

Answer 1

Try something like this:

var
  P: TPoint;  
  R1, R2, I: TRect;
begin
  P := TheComponent.ClientOrigin;
  R1 := TheComponent.ClientRect;
  Windows.OffsetRect(R1, P.X, P.Y);
  P := TheForm.ClientOrigin;
  R2 := TheForm.ClientRect;
  Windows.OffsetRect(R2, P.X, P.Y);
  if Windows.IntersectRect(I, R1, R2) then
    // the Form is over the component
  else
    // the Form is not over the component
end;