function myJsonp(url, data, callback) {

        //参数判断

        if (Object.prototype.toString.call(data) == "[object Function]") {

            callback = data;

            data = undefined;

        }

        //设置回调函数随机名称

        var cbFnName = "cb_" + Math.floor(Math.random() * 123456789).toString(32);

        this[cbFnName] = callback;

        //将data对象格式转换为aaa=bbb&ccc=ddd格式

        var stringIfyData = data != undefined ? Object.keys(data).map(function (key) {

            return encodeURIComponent(key) + "=" + encodeURIComponent(data[key]);

        }).join("&") + "&" : "";

        //生成script标签

        var scriptElement = document.createElement("script");

        scriptElement.src = url + (url.indexOf('?') > -1 ? '&' : '?') + stringIfyData + "callback=" + cbFnName;

        document.body.appendChild(scriptElement);

    }

    //调用豆瓣api-三个参数

    myJsonp("http://api.douban.com/v2/movie/top250", {name: "leyi"}, function (rps) {

        console.info("rps", rps);

    });

    //调用豆瓣api-两个参数

    myJsonp("http://api.douban.com/v2/movie/top250", function (rps) {

        console.info("rps", rps);

    });