JS实现AOP拦截方法调用

//JS实现AOP拦截方法调用
function jsAOP(obj,handlers) {
    if(typeof obj == 'function'){
        obj = obj.prototype;
    }
    for(var methodName in handlers){
        var _handlers = handlers[methodName];
        for(var handler in _handlers){
            if((handler == 'before' || handler == 'after') && typeof _handlers[handler] == 'function'){
                eval(handler)(obj,methodName,_handlers[handler]);
            }
        }
    }
//方法执行前
    function before(obj,method,f) {
        var original = obj[method]; 
        obj[method] = function() {
            var isSubmit = f.apply(this, arguments); 
            if(!isSubmit) return false;
            return original.apply(this, arguments);  
        }
    }
//方法执行后
    function after(obj,method, f) {  
        var original = obj[method];  
        obj[method] = function() {
         original.apply(this, arguments);  
            return f.apply(this, arguments);  
        }
    }
}
//调用方式；window：方法所在对象；doSubmit：拦截方法名称
jQuery(document).ready(function(){
 jsAOP(window,{'doSubmit':{before:function(){alert("before")},after:function(){alert("after")}}});
});