把一个空的Iframe放到DIV里面就好了，不能包着的自己的控件，并且宽度和高度要和DIV一样
<
div
id
='divForm'
style
='display:
none; position: absolute; z-index: 1000; background-color: White'
>
< CopyControl:CopyDiv runat ="server" ID ="CopyControl" >
</ CopyControl:CopyDiv >
< IFRAME width ="300px" height ="170px" style ="position:absolute; top:0px; z-index:-1; border-style:none; border-width:0px; border:0px" >
</ IFRAME >
</ div >
< CopyControl:CopyDiv runat ="server" ID ="CopyControl" >
</ CopyControl:CopyDiv >
< IFRAME width ="300px" height ="170px" style ="position:absolute; top:0px; z-index:-1; border-style:none; border-width:0px; border:0px" >
</ IFRAME >
</ div >