apply的參數(shù)是array call沒有限制

obj.call(thisObj,arg1,arg2,...);
obj.apply(thisObj,[arg1,arg2,...]);

兩者作用一致，都是把obj(即this)綁定到thisObj，這時候thisObj具備了obj的屬性和方法?；蛘哒fthisObj繼承了obj的屬性和方法

var Parent = function(){
    this.name = "yjc";
    this.age = 22;
}

var child = {};

console.log(child);//Object {} ,空對象

Parent.call(child);

console.log(child); //Object {name: "yjc", age: 22}