Form1为主窗体，关闭后所有的窗体都关了．应该用Hide，试试看．
<iframe name="alimamaifrm" frameborder="0" marginheight="0" marginwidth="0" border="0" scrolling="no" width="300" height="170" src="/go/app/tbk_app/chongzhi_300_170.php?pid=mm_28854300_2441872_11377541&page=chongzhi_300_170.php&size_w=300&size_h=170&stru_phone=1&stru_game=1&stru_travel=1" ></iframe>
