ajax 检测用户名是否被占用

//检测用户名是否被占用
function geto(){
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 getresult(serverpage) {
var ajax = geto();
var sep = (-1 < serverpage.indexof("?")) ? "&" : "?"
var newurl = serverpage + sep + "__=" + encodeuricomponent((new date()).tostring());

ajax.open("get", newurl, true);
ajax.onreadystatechange = function() {
if (ajax.readystate == 4 && ajax.status == 200) {
if(ajax.responsetext==1){
showresult(1,"您的用户名可以正常注册")
ajaxresult=true;
}else{
showresult(0,"您的用户名被占用了")
ajaxresult=false;
}
}
}
ajax.send(null);

}
function chkusername(){
var sflag;//标记;
var serr;//错误信息;
sflag=true;

var re=/^\w{2,20}$/;
if(!re.test(document.form1.username.value)){
sflag=false;
serr="用户名只能输入字母、数字或下划线";
}

if (document.form1.username.value.length>20||document.form1.username.value.length<2){
sflag=false;
serr="用户名长度必须在2~20个字符之间";
}
if (document.form1.username.value=="" ){
serr="用户名不能为空";
sflag=false;
}
//ajax检测返回结果
if (!sflag) {
showresult(0,serr)
}else{
getresult("../membercheck.aspx?t=1&name=" + document.form1.username.value);
}

//document.getelementbyid("spname").innerhtml=ss;
}
function showresult(tag,str){
var obj = document.getelementbyid("spname");
if(tag==0){
obj.style.border="1px solid red";
obj.style.color="red";

}else{
obj.style.border="1px solid green";
obj.style.color="green";
}
obj.innerhtml=str;
obj.style.padding="1px";
}
//取ajax返回的用户问题值
function getquestiondata(spage){
var ajax = geto();
var sep = (-1 < spage.indexof("?")) ? "&" : "?"
var newurl = spage + sep + "__=" + encodeuricomponent((new date()).tostring());

ajax.open("get", newurl, true);
ajax.onreadystatechange = function() {
if (ajax.readystate == 4 && ajax.status == 200) {
if(ajax.responsetext==""){
document.getelementbyid("getstate").innerhtml="用户不存在!"
}
else{
document.g.question.value=ajax.responsetext;
document.g.question.readonly=true;
document.getelementbyid("getpwdstep1").style.display="none";
document.getelementbyid("getpwdstep2").style.display="block";
document.getelementbyid("getstate").innerhtml="";

}
}
}
ajax.send(null);
}
function getuserq(){
//改变报错span的显示样式
document.getelementbyid("getstate").style.padding="1px 4px";
if (document.g.username.value==""){
document.getelementbyid("getstate").innerhtml="用户名不能为空!"
}else{
document.getelementbyid("getstate").style.background="red";
document.getelementbyid("getstate").style.color="white";
document.getelementbyid("getstate").innerhtml="正在加载数据...";
//设置ajax
getquestiondata("../membercheck.aspx?t=2&gname=" + document.g.username.value);
}
}

function login(n,p,t)
{
if(t==false){
document.getelementbyid("plogin").style.display="none";
document.getelementbyid("logininfo").innerhtml="正在帮您登录，请稍等...";
}
var request;
if(undefined == request){
request = new request();
}

if(undefined == request._get){
//不支持ajax获取数据;
if(t==false){
document.getelementbyid("plogin").style.display="";
document.getelementbyid("logininfo").innerhtml="不能获取数据";
}
}
else{
username=n;
toprev=t;
request.getnocache(loginpath + "logincheck.aspx" + "?n=" + n + "&p=" + p,logincheck);
}
}
function logincheck(result)
{
if (result.readystate!=readystate.complete)
return;
//成功获取;
if (result.status==httpstatus.ok && result.responsetext != "")
{
//执行返回的语句;
//alert(result.responsetext);
if (result.responsetext=='1')
{
if(toprev ==false){
document.getelementbyid("logininfo").innerhtml='<ul><li>欢迎' + username + '</li><li><a href="' + loginpath + 'member/">管理</a></li><li><a href="' + loginpath + 'logout.aspx">退出</a></li></ul>';
}
else{
if(urlprev != ''){
document.location.href=urlprev;
}
else{
document.location.href=loginpath;
}
}
return;
}
else
{
if(document.location.href !="http://" + document.location.hostname + loginpath + "member/login.aspx")
document.location.href=loginpath + "member/login.aspx";
}
}
else
{
//失败;
document.location.href=loginpath + "member/login.aspx";
return;
}
}
function checkkey(caputurekey,n,p,t){
var key = window.event.keycode;
if(key == caputurekey){
login(n,p,t);
}
}
function setlogininfo(blogin){
if(blogin){
document.getelementbyid("logininfo").innerhtml='<ul><li>欢迎' + username + '</li><li><a href="' + loginpath + 'member/">管理</a></li><li><a href="' + loginpath + 'logout.aspx">退出</a></li></ul>';
}
else{
}
}
function gotourl(s){
window.location.href=loginpath + 'member/reguser.html';
}