MoveSizeMode mockup

MoveSizeMode moveSizeMode = MoveSizeMode.Clear;

private void handleTopRight_MouseDown(object sender, MouseEventArgs e)
{
    moveSizeMode = (MoveSizeMode)(MoveSizeMode.Top | MoveSizeMode.Left);
}

private void handleTopRight_MouseUp(object sender, MouseEventArgs e)
{
    moveSizeMode = MoveSizeMode.Clear;
}

private void handleTopRight_MouseMove(object sender, MouseEventArgs e)
{
    if(moveSizeMode == (MoveSizeMode)(MoveSizeMode.Top | MoveSizeMode.Left))
    {
        // Do move code...
    }
}