function Foo() { this.x = 1; } Foo.prototype.getX = function() { return this.x; }; const foo = new Foo(); const getX = foo.getX; console.log(getX());
1
undefined
抛出TypeError
NaN
这道题你会答吗?花几分钟告诉大家答案吧!
扫描二维码,关注牛客网
下载牛客APP,随时随地刷题