# [C#]判斷星期幾 ###### tags: `c#` `DateTime` `Visual Studio` > [time= 2019 11 07 ] > 原文 & 參考: > https://king39461.pixnet.net/blog/post/269212351 <br> ```csharp= private static string GetDayName () { DateTime today = DateTime.Now; switch (today.DayOfWeek) { case DayOfWeek.Monday: return "星期一"; case DayOfWeek.Tuesday: return "星期二"; case DayOfWeek.Wednesday: return "星期三"; case DayOfWeek.Thursday: return "星期四"; case DayOfWeek.Friday: return "星期五"; case DayOfWeek.Saturday: return "星期六"; case DayOfWeek.Sunday: return "星期日"; } return "system error"; } ```