动态加载javascript增强版

我们经常使用动态加载Javascript，写个函数很容易现实，之前也写过一个函数，不过当加载多个JS时，只能根据浏览器返回的顺序来先后加载，这肯定不是我们想要的，现在使用了一下技巧，当加载多个JS时，能按照我们的顺序加载：

/*
    Name:动态加载JS
    Author:kingwell Leng
    Date : 2013/4/21
    E-mail: jinhua.leng##gmail.com

*/
function getScript(obj, callback) {
    var arr = obj,
    timeout,
    str = typeof obj === 'string';
    function add() {
        var script = document.createElement("script");
            header = document.getElementsByTagName("head")[0];
        script.src = str ? obj : arr[0];
        script.type = "text/javascript";
        if (str) {
            if (script.readyState) {
                script.onreadystatechange = function () {
                    if (script.readyState === 'loaded' || script.readyState === 'complete') {
                        script.onreadystatechange = null;
                        callback && callback();
                    }
                };
            } else {
                script.onload = function () {
                    callback && callback();
                };
            }
        } else {
            if (arr.length >= 1) {
                if (script.readyState) {
                    script.onreadystatechange = function () {
                        if (script.readyState === 'loaded' || script.readyState === 'complete') {
                            script.onreadystatechange = null;
                            arr.shift();
                            timeout = setTimeout(add, 1);
                        }
                    };
                } else {
                    script.onload = function () {
                        arr.shift();
                        timeout = setTimeout(add, 1);
                    };
                }
            } else {
                clearTimeout(timeout);
                callback && callback();
            }
        }
        header.appendChild(script);
    }
    add();
}

/*
    Name:动态加载JS
    Author:kingwell Leng
    Date : 2013/4/21
    E-mail: jinhua.leng##gmail.com

*/
function getScript(obj, callback) {
	var arr = obj,
	timeout,
	str = typeof obj === 'string';
	function add() {
		var script = document.createElement("script");
			header = document.getElementsByTagName("head")[0];
		script.src = str ? obj : arr[0];
		script.type = "text/javascript";
		if (str) {
			if (script.readyState) {
				script.onreadystatechange = function () {
					if (script.readyState === 'loaded' || script.readyState === 'complete') {
						script.onreadystatechange = null;
						callback && callback();
					}
				};
			} else {
				script.onload = function () {
					callback && callback();
				};
			}
		} else {
			if (arr.length >= 1) {
				if (script.readyState) {
					script.onreadystatechange = function () {
						if (script.readyState === 'loaded' || script.readyState === 'complete') {
							script.onreadystatechange = null;
							arr.shift();
							timeout = setTimeout(add, 1);
						}
					};
				} else {
					script.onload = function () {
						arr.shift();
						timeout = setTimeout(add, 1);
					};
				}
			} else {
				clearTimeout(timeout);
				callback && callback();
			}
		}
		header.appendChild(script);
	}
	add();
}

调用：

getScript(['http://code.jquery.com/jquery-1.9.1.min.js','js1.js', 'js2.js', 'js3.js', 'js4.js'], function () {
    alert('我是按顺序加载啦');
});

getScript(['http://code.jquery.com/jquery-1.9.1.min.js','js1.js', 'js2.js', 'js3.js', 'js4.js'], function () {
	alert('我是按顺序加载啦');
});

 现在是按照我们写代码的顺序加载啦...