Javascript在foreach循环中更改变量名称

Question

我希望在foreach循环中从对象更改变量名

const Foo = () => import('./Foo.vue')

Answer 1

var days = ['monday','tuesday', 'wednesday', 'thursday', 'friday', 'saturday', 'sunday'];

days.forEach(function(day){
  console.log(agency.openingHours[day].opening)

})

您没有更改变量名称，并且也没有更改。您遍历openingHours对象的键。这样会更正确

Answer 2

您可以使用days.map（）代替days.forEach，因为map（）返回一个新数组。

请参阅：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map

Answer 3

agency.openingHours[day].opening-与bracket notation（agency.openingHours['Monday'].opening）访问对象属性相同，只是不引用变量。

var days = ['monday','tuesday', 'wednesday'];

const agency = {
  openingHours: {
    monday: { opening: '0900' },
    tuesday: { opening: '0500' },
    wednesday: { opening: '1000' }
  }
}

days.forEach(function(day, index) {
  console.log(agency.openingHours[day].opening);
});