<script type="text/javascript" language="javascript">
        <!--
        //以xml求取数据
        function xmlpost(theemail)
        {
　　        var webfileurl = "../user/checkuser.aspx?logonname=" + theemail;
　　        var result = "";
　　        　　       
　　        if (window.activexobject) {
            xmlhttp = new activexobject("microsoft.xmlhttp");
            }
            else if (window.xmlhttprequest) {
            xmlhttp = new xmlhttprequest();
            }

　　        //var xmlhttp = new activexobject("msxml2.xmlhttp");
　　        xmlhttp.open("post", webfileurl, false);
　　        xmlhttp.setrequestheader("content-type","application/x-www-form-urlencoded");   
　　        xmlhttp.send("");　　    　　       
　　               
            xmlhttp.onreadystatechange=function()
            {
                if (xmlhttp.readystate==4)
                {
                    result = xmlhttp.responsetext;
                }
            }
            if(xmlhttp.status!=200)
            {
                alert ('网络故障(xmlhttp.status='+xmlhttp.status+')，请稍后再试！');
            }
               
            result = xmlhttp.responsetext;　
　　        result = result.substring(0,result.indexof("?ex"));
　　       
　　        if(result != "false")
　　        {　　　　       
　　　　        return true;
　　        }
　　        else
　　        {
　　　　        return false;
　　        }
        }
        //-->
    </script>''' <summary>
''' 检测用户是否存在<文件名：../user/checkuser.aspx>
''' </summary>
''' <remarks>created by dzh @2006/06/27 18:22</remarks>
partial class web_user_checkuser
    inherits system.web.ui.page

    protected sub page_load(byval sender as object, byval e as system.eventargs) handles me.load
        if request.querystring("logonname") is nothing then
            response.write("false" + "?ex")
            response.end()
            exit sub
        end if

        if (new easyclick.easybusiness.userbusiness).getuserbylogonname(request.querystring("logonname").tostring) is nothing then[来源www.iocblog.net]
            response.write("false" + "?ex")
            response.end()
            exit sub
        else
            response.write("true" + "?ex")
            response.end()
            exit sub
        end if
    end sub
end class
[来源www.iocblog.net]