javascrip 自封装document.ready方法

/*
*DOM内容加载完毕后执行脚本代码(Dom标签加载完毕后执行代码）
* fn：待执行的函数
* scope: fn的执行作用域
*/
document.domReady = function (fn, scope) {
    var doc = document,
        readyFn = null;

    //W3C标准
    if (doc.addEventListener) {
        readyFn = function () {
            doc.removeEventListener('DOMContentLoaded', readyFn, false);
            fn.apply(scope);
        };
        doc.addEventListener('DOMContentLoaded', readyFn, false);
    }

    /*IE下*/
    if (doc.attachEvent) {
        readyFn = function () {
            if (doc.readyState == 'complete' && !readyFn.done) {
                readyFn.done = true;
                fn.apply(scope);

                doc.detachEvent('onreadystatechange', readyFn);
                window.detachEvent('onload', readyFn);
            }
        };

        doc.attachEvent('onreadystatechange', readyFn);
        window.attachEvent('onload', readyFn);

        void function () {
            if (readyFn.done) {
                return;
            }

            try {
                document.documentElement.doScroll("left");
            } catch (e) {
                setTimeout(arguments.callee, 1);
                return;
            }

            readyFn.done = true;
            fn.apply(scope);
        } ();
    }
};