方法一:<a href="javascript:MM_openBrWindow('SendPass_Edit.aspx','ModiWin','width=440,height=270')">点击</a>
方法二:
            Button1.Attributes.Add("onClick", "javascript:MM_openBrWindow('SendPass_Edit.aspx','ModiWin','width=440,height=270')")
在页面head中间放上下边的
<script language="JavaScript" type="text/JavaScript">
<!--
function MM_openBrWindow(theURL,winName,features) { //v2.0
window.open(theURL,winName,features);
}
//-->
</script>