Перетаскивание формы

void __fastcall TForm3::Image1MouseUp(TObject *Sender, TMouseButton Button, TShiftState Shift,
          int X, int Y)
{
 long SC_DRAGMOVE = 0xF012;
 if(Button == mbLeft)
  {
  ReleaseCapture();
  SendMessage(Handle, WM_SYSCOMMAND, SC_DRAGMOVE, 0);
 }
}

bool Pressed(false);
 
void __fastcall TForm1::Image1MouseMove(TObject *Sender, TShiftState Shift, int X, int Y) {
    long SC_DRAGMOVE = 0xF012;
    if (Pressed) {
        ReleaseCapture();
        SendMessage(Handle, WM_SYSCOMMAND, SC_DRAGMOVE, 0);
    }
}
 
// ---------------------------------------------------------------------------
void __fastcall TForm1::Image1MouseDown(TObject *Sender, TMouseButton Button, TShiftState Shift, int X, int Y) {
    Pressed = true;
}
 
// ---------------------------------------------------------------------------
void __fastcall TForm1::Image1MouseUp(TObject *Sender, TMouseButton Button, TShiftState Shift, int X, int Y) {
    Pressed = false;
}
// ---------------------------------------------------------------------------