javascript hook

function js_hook(_obj,_fn_name,_hook_call) {
    var _class = _obj;
    if(typeof _obj === "function"){
        _class = _obj.constructor;
    };
    var original = _class[_fn_name];
    _class[_fn_name] = function () {
        return _hook_call.call(this,original,arguments);
    };
};

使用方法

js_hook(document,"write",function (org,args) {
    console.debug(args);
    args[0] = "hook_"+args[0];
    org.apply(this,args);
});
document.write("test");