MyClass = function () { this.A = 1; } MyClass.prototype.X = function () { this.B = 2; } MyClass.prototype.Y = function () { this.Z = function () { this.C = 3; } } /* 内部对象的 this ? */ obj = new MyClass(); alert(obj.A); //1 obj1 = new obj.X(); alert(obj1.B); //2 obj2 = new (new obj.Y()).Z(); alert(obj2.C); //3 /* 所属对象的 this ? */ obj = new MyClass(); obj.X(); obj.Y(); obj.Z(); alert(obj.A); //1 alert(obj.B); //2 alert(obj.C); //3