怎样用JS模拟实现枚举

在当前的JavaScript中，并没有枚举这个概念，在某些场景中使用枚举更能保证数据的正确性，减少数据校验过程，下面就介绍一下JavaScript如何模拟实现枚举效果。

let days;(function (days) { days[days['Sunday'] = 0] = 'Sunday'; days[days['Monday'] = 1] = 'Monday'; days[days['Tuesday'] = 2] = 'Tuesday'; days[days['Wednesday'] = 3] = 'Wednesday'; days[days['Thursday'] = 4] = 'Thursday'; days[days['Friday'] = 5] = 'Friday'; days[days['Saturday'] = 6] = 'Saturday';})(days || (days = {}));

这个时候days对象基本实现了枚举效果，可以通过枚举值或索引去访问days对象，但枚举有个重要特别是不能被修改，这个时候days是可以随意修改的；可以通过Object.freeze函数让对象不改修改，重新导出一个不可以修改的对象，完整代码如下：

let days;(function (days) { days[days['Monday'] = 1] = 'Monday'; days[days['Tuesday'] = 2] = 'Tuesday'; days[days['Wednesday'] = 3] = 'Wednesday'; days[days['Thursday'] = 4] = 'Thursday'; days[days['Friday'] = 5] = 'Friday'; days[days['Saturday'] = 6] = 'Saturday'; days[days['Sunday'] = 0] = 'Sunday';})(days || (days = {}));//导出可枚举对象export EnumWeek = Object.freeze(days)

以上就是怎样用JS模拟实现枚举的详细内容，更多关于JS的资料请关注好吧啦网其它相关文章！