AJAX没反应
function getObject(){
var ajax=false;
try {
ajax = new ActiveXObject("MSXML2.XMLHTTP");
} catch (e) {
try {
ajax = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {
ajax = false;
}
}
if (!ajax && typeof XMLHttpRequest!='undefined') {
ajax = new XMLHttpRequest();
}
return ajax;
}
function chechUsernameExist()
{
var obj=document.getElementById('registerName');
var registerName=obj.value;
if(registerName=="")
{
alert('请先检查输入的合法性');
obj.focus();
return false;
}
else
{
var ajaxObj=getObject();
if(ajaxObj)
{
var URL="checkName.php?registerName="+registerName;
ajaxObj.open("GET",URL,false);
ajaxObj.onreadystatechange=function()
{
if(ajaxObj.readyState==4&&ajaxObj.status==200)
{
switch(parseInt(ajaxObj.responseText))
{
case 1:
alert("恭喜您,此用户名可以注册");
return true;
case 2:
alert("对不起,此用户名已被注册");
return false;
default:
alert("对不起,此用户名已被注册");
return false;
}
}
}
ajaxObj.send(null);
}
}
}