AJAX asp 查询数据库并得到返回值

function checkdomain(){
var domain = document.getelementbyid("domain").value;
if(domain == ''){
alert("请填写域名！");
document.getelementbyid("domain").focus();
return false;
}
var info=domain.match(/^[a-z0-9]+$/);
if(!info){
alert("域名必须是字母和数字组成！");
document.getelementbyid("domain").focus();
return false;
}else{
var xml=window.activexobject ? new activexobject("microsoft.xmlhttp") : new xmlhttprequest();
xml.open('get','/index.asp?r=company/checkdomain&domain='+domain,true);
xml.send('');
xml.onreadystatechange = function()
{
if(xml.readystate == 4 && xml.status == 200)
{
var result = xml.responsetext;
document.getelementbyid("result").innerhtml = result;
}
}
}
}

asp代码

'-----------------------------------------------------------------
dim username
username=trim(request.form("username")) '接收ajax发送的参数
if username="" then response.end()
'------------------------------------------------------------------
set rs=server.createobject("adodb.recordset")
sql="select * from test where username = '"&username&"'"
rs.open sql,conn,1,1
'------------------------------------------------------------------
'--------如果没有找到的话,返回0
'--------如果找到的话,返回所有匹配的项目
if not (rs.eof and rs.bof) then
response.write(""&rs("time")&"")
rs.close
set rs=nothing
%>