📅  最后修改于: 2022-03-11 15:02:50.732000             🧑  作者: Mango
'use strict';
var obj = {
a: 10
b:20
};
Object.defineProperty(obj, 'b', {
get: () => {
console.log(this.a, typeof this.a, this); // undefined 'undefined' Window {...} (or the global object)
return this.a + 10; // represents global object 'Window', therefore 'this.a' returns 'undefined'
}
});