constobj={say:function(name){console.log("sayhello"+name);}};constaddSay=()=>{console.log("addSay");};varoldMethod=obj["say"];obj["say"]=function(arg){addSay.call(this,arg);returnoldMethod.call.apply(oldMethod,[this].concat(Array.prototype.slice.call(arguments)));};obj.say("allen");代碼如上，其中這塊代碼看不懂，有懂的么obj["say"]=function(arg){addSay.call(this,arg);returnoldMethod.call.apply(oldMethod,[this].concat(Array.prototype.slice.call(arguments)));};