Как сделать чтоб Image при передвижении не выходил за границы формы?

void __fastcall TForm3::FormKeyDown(TObject *Sender, WORD &Key, TShiftState Shift)
 
{
 switch(Key)
    {
case VK_LEFT: this->leftright = -5;break;
case VK_RIGHT: this->leftright = 5;break;
case VK_UP: this->updown = -5;break;
case VK_DOWN: this->updown = 5;break;
}
}
//---------------------------------------------------------------------------
 
void __fastcall TForm3::FormKeyUp(TObject *Sender, WORD &Key, TShiftState Shift)
{
 if ((Key==VK_LEFT)||(Key==VK_RIGHT)) this->leftright = 0;
    if ((Key==VK_UP)||(Key==VK_DOWN)) this->updown = 0;
}
//---------------------------------------------------------------------------
void __fastcall TForm3::Timer1Timer(TObject *Sender)
{
this->Image1->Left += this->leftright;
this->Image1->Top += this->updown;
this->Image2->Left += this->leftright;
}

void __fastcall TGeneral::Timer1Timer(TObject *Sender)
{
if (this->Image1->Left + this->leftright + this->Image1->ClientWidth <= General->ClientWidth  && this->Image1->Left + this->leftright >= 0) {
  this->Image1->Left += this->leftright;
}
if (this->Image1->Top + this->updown + this->Image1->ClientHeight <= General->ClientHeight  && this->Image1->Top + this->updown >= 0) {
 this->Image1->Top += this->updown;
}
}

class TForm1 : public TForm
{
__published:    // IDE-managed Components
    // здесь компоненты - не трогаем
 
private:
    int updown, leftright; // <--- Вот они
public:
    __fastcall TForm1(TComponent* Owner);
};