发布我的Ajax工具类（myAjax）。可解决UTF8客户端获取GB2312的服务器端出现的乱码问题

大多数的客户端都采用UTF-8编码，这也是现在实现国际化最常用的编码格式

在这种情况下，实用AJAX异步获取GB2312编码的服务器端信息时，不可避免的要遇到汉字乱码问题

因为目标数据是GB2312，但XMLHttpRequest默认是用UTF-8来进行数据封装的，因此会产生乱码

相信很多人都在用轻量级的JS工具集-prototype.js，它的AJAX功能同样很出色

我也一直在用它，因此对于这个问题也一直是基于 prototype.js来考虑的

但经过多次试验，还是没能把它返回的 responseText 转成正确的编码格式

后来了解到，在XMLHttpRequest对象的 responseBody 属性中，保存了原始的数据信息

但prototype.js的AJAX功能返回的 responseBody 属性是 undefined，看来还是要自己动手了

经过近一个小时的敲打，一个短小精悍的AJAX框架腾空出世了，哈哈，不过功能还是很全的

调用方式及注释：

myAjaxCall({      
    url : 'xxxxx.jsp' //目标页面地址      
    ,params : URLEncoding('prm1=参数1&prm2=参数2') //参数串信息      
    ,method : 'POST' //发送方式POST or GET      
    ,callBack : retValue //回调函数名称      
    ,isBody : true //是否返回 responseBody ，默认返回 responseText      
    //,isXml : false //是否以XML格式返回数据      
    //,errorReport : false //发送错误时，是否弹出提示      
    //,attachs : {} //附加的其他参数，可传递给回调函数      
});      
function retValue(res,att){      
    var strRet = bytes2BSTR(res);      
    alert(strRet);      
}

注意看其中的两个函数：

1、URLEncoding ：对参数进行编码
2、bytes2BSTR ：对返回的数据进行解码

这两个函数直接借鉴了网络上很流行的两个编码函数，不过都是用vbs写的
需要把这两个函数也附加到上面的页面里：

Function URLEncoding(vstrIn)   
    strReturn = ""   
    For i = 1 To Len(vstrIn)   
        ThisChr = Mid(vStrIn,i,1)   
        If Abs(Asc(ThisChr)) < &HFF Then   
            strReturn = strReturn & ThisChr   
        Else   
            innerCode = Asc(ThisChr)   
            If innerCode < 0 Then   
                innerCode = innerCode + &H10000   
            End If   
            Hight8 = (innerCode  And &HFF00) \ &HFF   
            Low8 = innerCode And &HFF   
            strReturn = strReturn & "%" & Hex(Hight8) &  "%" & Hex(Low8)   
     End If   
    Next   
    URLEncoding = strReturn   
End Function   
Function bytes2BSTR(vIn)   
    strReturn = ""   
    For i = 1 To LenB(vIn)   
        ThisCharCode = AscB(MidB(vIn,i,1))   
        If ThisCharCode < &H80 Then   
            strReturn = strReturn & Chr(ThisCharCode)   
        Else   
            NextCharCode = AscB(MidB(vIn,i+1,1))   
            strReturn = strReturn & Chr(CLng(ThisCharCode) * &H100 + CInt(NextCharCode))   
            i = i + 1   
        End If   
    Next   
    bytes2BSTR = strReturn   
End Function

下面附上我写的轻量级Ajax框架 - myAjax.js 源码：

/**
 * Ajax工具类: myAjax
 * @author     网无忌(netwild)
 * @email      inetwild@gmail.com
 * @qq         52100641
 * @version    1.0
 */
var myAjaxConfig = {   
    "url":""   
    ,"params":""   
    ,"method":"GET"   
    ,"callBack":function(){}   
    ,"isXml":false   
    ,"isBody":false   
    ,"isCache":false   
    ,"errorReport":true   
    ,"statePoll":null   
    ,"postData":null   
    ,"attachs":{}   
};   
function myAjaxCall(requestJson){   
    var attach;   
    if(requestJson && typeof requestJson == "object"){   
        if(requestJson.url){myAjaxConfig.url = requestJson.url;}   
        if(requestJson.params){myAjaxConfig.params = requestJson.params;}   
        if(requestJson.method){myAjaxConfig.method = requestJson.method;}   
        if(requestJson.callBack){myAjaxConfig.callBack = requestJson.callBack;}   
        if(requestJson.isXml){myAjaxConfig.isXml = requestJson.isXml;}   
        if(requestJson.isBody){myAjaxConfig.isBody = requestJson.isBody;}   
        if(requestJson.isCache){myAjaxConfig.isCache = requestJson.isCache;}   
        if(requestJson.statePoll){myAjaxConfig.statePoll = requestJson.statePoll;}   
        if(requestJson.attachs){myAjaxConfig.attachs = requestJson.attachs;}   
    }   
    if(!myAjaxConfig.isCache){   
        var nocache = new Date().getTime();   
        if(myAjaxConfig.url.indexOf("?")>0){myAjaxConfig.url += "&nocache=" + nocache;}   
        else{myAjaxConfig.url += "?nocache=" + nocache;}   
    }   
    var newCall = new myAjaxCore();   
    newCall.init();   
}   
function myAjaxCore(){   
    var _self = this;   
    var _state,_status;   
    var _httpRequest,_attach;   
    ////////////////////////////////////////////////////   
    this.init = function(){   
        if (window.XMLHttpRequest){   
            _httpRequest = new XMLHttpRequest();   
            if (_httpRequest.overrideMimeType) _httpRequest.overrideMimeType('text/xml'); 
        }else if (window.ActiveXObject) {   
            var MSXML = ['MSXML2.XMLHTTP.6.0','MSXML2.XMLHTTP.3.0','MSXML2.XMLHTTP.5.0','MSXML2.XMLHTTP.4.0','MSXML2.XMLHTTP', 'Microsoft.XMLHTTP'];   
            for(var n=0;n<MSXML.length;n++){    
                try {    
                    _httpRequest = new ActiveXObject(MSXML[n]);    
                    break;    
                }catch(e){}   
            }    
        }   
        with(_httpRequest) {   
            onreadystatechange = _self.getResponse;   
            open(myAjaxConfig.method,myAjaxConfig.url,true);   
            if(myAjaxConfig.method == "POST" && (myAjaxConfig.params != "")){   
                setRequestHeader("Content-Length",myAjaxConfig.params.length);      
                setRequestHeader("Content-Type","application/x-www-form-urlencoded");   
                send(myAjaxConfig.params);   
            }else{   
                var textType = myAjaxConfig.isXml?"text/xml":"text/plain";   
                _httpRequest.setRequestHeader('Content-Type',textType);   
                if(browser.IE) setRequestHeader("Accept-Encoding", "gzip, deflate");   
                else if(browser.FF) setRequestHeader("Connection","close");   
                send(null);   
            }   
        }   
    };   
    ////////////////////////////////////////////////////   
    this.getResponse = function(){   
        _state = _httpRequest.readyState;   
        if(_httpRequest.readyState == 4 && _httpRequest.status){_status = _httpRequest.status;}   
        if(myAjaxConfig.statePoll){myAjaxConfig.statePoll(_httpRequest.readyState);}   
        if(_httpRequest.readyState==4 && _httpRequest.status>=400){   
            _self.abort();   
            _self.alertf("ERROR:HTTP response code "+_httpRequest.status);   
        }   
        if(_httpRequest.readyState==4 && _httpRequest.status==200){   
            var response_content;   
            if(myAjaxConfig.isXML){   
                response_content = _httpRequest.responseXML;   
            }else if(myAjaxConfig.isBody){   
                response_content = _httpRequest.responseBody;      
            }else{   
                response_content = _httpRequest.responseText;   
            }          
            if(typeof myAjaxConfig.callBack == "function"){   
                myAjaxConfig.callBack(response_content,myAjaxConfig.attachs);   
            }else{   
                eval(myAjaxConfig.callBack+"(response_content,myAjaxConfig.attachs)");   
            }   
        }   
    };   
    ////////////////////////////////////////////////////   
    this.abort=function(){_httpRequest.abort();};   
    this.state=function(){return _state;};   
    this.status=function(){return _status;};   
    this.destory=function(){_self.abort();delete(_httpRequest);};   
    this.alertf=function(error){if(myAjaxConfig.errorReport){alert(error);}};   
}   
if(!browser){   
    var browser={};   
    browser.IE = browser.ie = window.navigator.userAgent.indexOf("MSIE")>0;   
    browser.Firefox = browser.firefox = browser.FF = browser.MF = navigator.userAgent.indexOf("Firefox")>0;   
    browser.Gecko = browser.gecko = navigator.userAgent.indexOf("Gecko")>0;   
    browser.Safari = browser.safari=navigator.userAgent.indexOf("Safari")>0;   
    browser.Camino = browser.camino=navigator.userAgent.indexOf("Camino")>0;   
    browser.Opera = browser.opera=navigator.userAgent.indexOf("Opera")>0;   
    browser.other = browser.OT=!(browser.IE || browser.FF || browser.Safari || browser.Camino || browser.Opera);   
}