在當前的JavaScript中，并沒有枚舉這個概念，在某些場景中使用枚舉更能保證數據的正確性，減少數據校驗過程，下面就介紹一下JavaScript如何模擬實現枚舉效果。

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 = {}));

這個時候days對象基本實現了枚舉效果，可以通過枚舉值或索引去訪問days對象，但枚舉有個重要特別是不能被修改，這個時候days是可以隨意修改的；可以通過Object.freeze函數讓對象不改修改，重新導出一個不可以修改的對象，完整代碼如下：

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 = {}));//導出可枚舉對象export EnumWeek = Object.freeze(days)

以上就是怎樣用JS模擬實現枚舉的詳細內容，更多關于JS的資料請關注好吧啦網其它相關文章！