ajax函数,用户注册_检测

var xmlHttp;ajax函数,用户注册_检测

//定义AJAX函数
function ajax() {

        if(window.XMLHttpRequest)
        {
            xmlHttp = new XMLHttpRequest();//mozilla浏览器
        }
        else if(window.ActiveXObject)
        {
            try
            {
             xmlHttp = new ActiveX0bject("Msxml2.XMLHTTP");//IE老版本
            }
            catch(e)
            {}
            try
            {
                xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");//IE新版本
            }
            catch(e)
            {}
            if(!xmlHttp)
            {
                window.alert("不能创建XMLHttpRequest对象实例");
                return false;
            }
        }
}

//GET方式
function ajaxget(url,allid) {

        ajax();//调用ajax函数

        xmlHttp.onreadystatechange = function(){
        if (xmlHttp.readyState == 4) {
            if (xmlHttp.status == 200) {
                document.getElementById(allid).innerHTML = xmlHttp.responseText;
            } else {
                document.getElementById(allid).innerHTML = "请求失败!";
            }
        }
        }
        xmlHttp.open('GET', url, true);
        xmlHttp.send(null);
}

//POST方式带数据
function ajaxpost(url,allid,form_obj) {

        //获取指定表单名当中所有值
        var theform = function(){
        var query_string='';
        var and='';
        //alert(form_obj.length);
        for (i=0;i<form_obj.length ;i++ )
        {
        e=form_obj;
        if (e.name!='')
        {
        if (e.type=='select-one')
        {
        element_value=e.options[e.selectedIndex].value;
        }
        else if (e.type=='checkbox' || e.type=='radio')
        {
        if (e.checked==false)
        {
        break;
        }
        element_value=e.value;
        }
        else
        {
        element_value=e.value;
        }
        query_string+=and+e.name+'='+element_value.replace(/\&/g,"%26");
        and="&"
        }
        }
        return query_string;
        }//获取结束

        var thispost = theform();//把表单获取的值赋给该变量

        ajax();//调用ajax函数

        xmlHttp.onreadystatechange = function(){
        if (xmlHttp.readyState == 4) {
            if (xmlHttp.status == 200) {
                document.getElementById(allid).innerHTML = xmlHttp.responseText;
            } else {
                document.getElementById(allid).innerHTML = "请求失败!";
            }
        }
        }
        xmlHttp.open('POST', url, true);
        xmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
        xmlHttp.send(thispost);//发送thispost表单数据
}