<input type ="button "
oncick = "OpenThenSetValue(B页路径,550,310,window,document.aspnetForm.gif_url)"
>
function OpenThenSetValue(Url,Width,Height,WindowObj,SetObj)
{
var ReturnStr=showModalDialog(Url,WindowObj,'dialogWidth:'+Width+'pt;dialogHeight:'+Height+'pt;status:no;help:no;scroll:no;status:0;help:0;scroll:0;');
if (ReturnStr!='')
{