自己写了个jsonp

  最近公司要跨域请求一个服务，服务未启动的时候还要报错。自己做了一个以符合业务需求
  
  
 贴上源码：
        
        希望大家能多多提意见
        
        /**

• v 1.0
• author xingzheng
• date 2018-12-19

*/
var JSONP = {

    now : function() {
        return (new Date()).getTime();
    },
    rand : function() {
        return Math.random().toString().substr(2);
    },
    waitPostArr:[],
    currentNodeName: "",
    
    removeElem : function(elem) {
        try{
            var parent = elem.parentNode;
            if (parent && parent.nodeType !== 11) {
                parent.removeChild(elem);
            }
        }catch(e){
            console.log(e);
        }
        
    },
    parseData : function(data) {
        var ret = "";
        if (typeof data === "string") {
            ret = data;
        } else if (typeof data === "object") {
            for ( var key in data) {
                ret += "&" + key + "=" + encodeURIComponent(data[key]);
            }
        }
        ret += "&_time=" + this.now();
        ret = ret.substr(1);
        return ret;
    },
    
    getJSONS : function(arr){
        this.waitPostArr = arr;
        this.getJSON(arr[0].url, arr[0].data, arr[0].func);
        this.waitPostArr.splice(0, 1);
    },
    getJSON : function(url, data, func) {
        var name;
        if(url.url){                    
            url = url + (url.url.indexOf("?") === -1 ? "?" : "&")
                + this.parseData(data);
        }else{
            url = url + (url.indexOf("?") === -1 ? "?" : "&")
                + this.parseData(data);
        }
        var match = /callback=(\w+)/.exec(url);
        if (match && match[1]) {
            name = match[1];
        } else {
            name = "jsonp_" + this.now() + '_' + this.rand();
            url = url.replace("callback=?", "callback=" + name);
            url = url.replace("callback=%3F", "callback=" + name);
        }
        var script = document.createElement("script");
        script.type = "text/javascript";
        script.src = url;
        script.id = "id_" + name;            
        script.onerror = function() {
            try{
                func({
                    result : "connectFailed"
                });
            }catch(e){
                JSONP.JSONP_next();
            }
            
        };
        var head = document.getElementsByTagName("head");
        if (head && head[0]) {
            head[0].appendChild(script);
        }
        this.currentNodeName = name;
    },
    JSONP_next : function(){
        if(this.waitPostArr && this.waitPostArr.length > 0){
            this.getJSON(this.waitPostArr[0].url, this.waitPostArr[0].data, this.waitPostArr[0].func);
            this.waitPostArr.splice(0, 1);
        }
    }
};
window["success_jsonpCallback"] = function(json) {
    var elem = document.getElementById("id_" + JSONP.currentNodeName);
    JSONP.removeElem(elem);
    try{
        func(json);
        JSONP.JSONP_next();
    }catch(e){
        JSONP.JSONP_next()
    }
};

给windows赋函数的时候没有采取一个请求一个函数是因为后台服务参数没有函数名称（WTF）