EP ep = new EP();//实例化一个对象
SqlConnection con = new SqlConnection(EP.GetConStr());
con.Open();//打开数据库连接
//检查
string userName = context.Request.QueryString["user"].ToString();
string SqlStr = "select * from Register where UserName=" + userName;
SqlCommand com = new SqlCommand(SqlStr, con);
SqlDataAdapter sda = new SqlDataAdapter(com);
DataSet ds = new DataSet();
sda.Fill(ds, "Register");
if (ds.Tables["Register"].Rows.Count > 0)
{
userName = ds.Tables["Register"].Rows[0]["UserName"].ToString();
context.Response.Write("Y");
}
else context.Response.Write("N"); context.Response.Flush();
<script language="javascript" type="text/javascript">
var xmlHttp;
function createXmlRequest()
{
if(window.ActiveXObject)
{
var xmlHttps=["MSXML2.XMLHttp.5.0","MSXML2.XMLHttp4.0",
"MSXML2.XMLHttp3.0","MSXML2.XMLHttp","Microsoft.XMLHTTP"];
try
{
for(var i=0;i<xmlHttps.length;i++)
{
var xmlHttp=new ActiveXObject(xmlHttps[i]);
return xmlHttp;
}
}
catch (error)
{
}
}
else
{
var xmlHttp=new XMLHttpRequest();
return xmlHttp;
}
throw new Error("失败");
}
function checkName(){
xmlHttp=createXmlRequest();
xmlHttp.onreadystatechange=handleStateChange;
xmlHttp.open("GET","Handler.ashx?user="+document.getElementById("TxtName").value+"",true);
xmlHttp.send(null);
}
function handleStateChange(){
if(xmlHttp.readyState==4){
if(xmlHttp.responseText=="Y")document.getElementById("divNameError").innerHTML="sorry 有人注册";
else document.getElementById("divNameError").innerHTML="";
}
}
</script>
大家给的答案,我改了下...我很笨,不知道哪里错了....指教下!@