js封装xhr【重复造轮子】

仿jquery ajax，不过功能没那么多。贴代码

--------------------------------------分割线------------------------------------------

//MyXhr对象
var MyXhr = function(config){
    this.config = config;
    var that = this;
    //默认配置项
    defaultConfig = {
        "options":{
                "url"    : "",//请求地址
                "method" : "post",//get||post
                "async"  : true,//异步
                "data"   : [],//post请求数据
                "timeout": 5000//超时时间
            },
        "success":function(){

        },
        "error":function(){

        }
    };
    //合并配置项
    var mergeConfig = this.config = this.extend(this.config, defaultConfig);
    var xhr = this.createXhr();

    //处理逻辑
    var postData = null;
    var url = mergeConfig.options.url;
    if(mergeConfig.options.method == "post"){
        //post 用formate传值，省去加header
        postData = mergeConfig.options.data;
        var formData = new FormData();
        for(var item in postData){
            formData.append(item, postData[item]);
        }
        postData = formData;
    }else{
        //get方式用参数名和参数值用encodeURIComponent()编码
        url = this.dealUrl(url);
    }
    xhr.open(mergeConfig.options.method, url, mergeConfig.options.async);

    xhr.onreadystatechange = function(){
        //监听状态 0=>为初始化 1=>启动 2=>发送 3=>接受 4=>完成
        if(xhr.readyState == 4){
            if((xhr.status>=200 && xhr.status<300) || xhr.status==304){
                that.config.success(xhr.responseText);
            }else{
                that.config.error()+xhr.status;
            }
        }
    };
    xhr.send(postData);

    //超时报错
    xhr.ontimeout = function(){
        throw new Error("connect timeout");
    }
}

/**以下为公共方法**/
//extend方法，与$.extend()相同
MyXhr.prototype.extend = function (p1, p2){
        var p = (function loop(p1, p2){
            var p = {};//返回值
            for(var item in p2){
                //如果是对象再次递归调用函数
                if(typeof p2[item]==='object'){
                    p[item] = loop(p1[item], p2[item]);
                }else{
                    /**自定义配置项覆盖默认配置**/
                    if((typeof p1)!='undefined' && (typeof p1[item])!='undefined' && p1[item]){
                        p[item] = p1[item];
                    }else{
                        p[item] = p2[item];
                    }
                }
            }
            return p;
        })(p1,p2);
        return p;s
};

//创建xhr
/**支持XHR对象和ActiveX对象**/
MyXhr.prototype.createXhr = function(){
    if(typeof XMLHttpRequest != "undefined"){
        return new XMLHttpRequest();
    }else if(typeof ActiveXObject != "undefined"){
        if(typeof arguments.callee.activeXString != "string"){
            var versions = ["MSXML2.XMLHttp.6.0", "MSXML2.XMLHttp.3.0", "MSXML2.XMLHttp"];
            var i, len;
            for(i = o,len=versions.length; i<len; i++){
                try{
                    new ActiveXObject(version[i]);
                    arguments.callee.activeXString = version[i];
                    break;
                }catch(ex){
                    //跳过
                }
            }
        }
        return new ActiveXObject(arguments.callee.activeXString);
    }else{
        throw new Error("NO XHR object available");
    }
}

//处理url
MyXhr.prototype.dealUrl = function(url){
    var index = url.indexOf('?');
    if(index == -1){
        return url;
    }
    var domain = url.substring(0, index);
    var pars = url.slice(index+1);
    var arrs = pars.split('&');
    var newurl = domain;
    for(var item in arrs){
        var arr = arrs[item].split("=");
        var split = "&";
        if(item == 0){
            split = "?";
        }
        newurl += (split + encodeURIComponent(arr[0]) + "=" + encodeURIComponent(arr[1]));
    }
    return newurl;

}

使用方法:

var xhr = new MyXhr({
            "options":{
                "method":"post",
                "url":"http://example.com/searchGoods"
            },
            "success":function(data){
                console.log(data);
            },
            "error":function(){
                console.log('error');
            }
        });