consta={}constb={key:'b'}constc={key:'c'}a[b]=123a[c]=456console.log(a[b])A:123B:456C:undefinedD:ReferenceError参考答案
consta={}constb={key:'b'}constc={key:'c'}a[b]=123a[c]=456console.log(a[b])A:123B:456C:undefinedD:ReferenceError参考答案