C#/.NET/.NET Core应用程序编程开发中如何获取指定日期所在周的第一天？

3 个回答

• 0

  创建一个日期的扩展方法，如下：

  public static class DateTimeExtensions
  {
      public static DateTime StartOfWeek(this DateTime dt, DayOfWeek startOfWeek)
      {
          int diff = (7 + (dt.DayOfWeek - startOfWeek)) % 7;
          return dt.AddDays(-1 * diff).Date;
      }
  }
  

  调用示例如下：

  DateTime dt = DateTime.Now.StartOfWeek(DayOfWeek.Monday);
  DateTime dt = DateTime.Now.StartOfWeek(DayOfWeek.Sunday);
  

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  Rector

  2020-05-18 回答
• 0

  使用Fluent DateTime第三方类库，示例如下：

  var monday = DateTime.Now.Previous(DayOfWeek.Monday);
  var sunday = DateTime.Now.Previous(DayOfWeek.Sunday);
  

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  Rector

  2020-05-18 回答
• 0

  使用操作系统默认的每周第一天，示例如下：

  public static DateTime FirstDateInWeek(this DateTime dt)
  {
      while (dt.DayOfWeek != System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.FirstDayOfWeek)
          dt = dt.AddDays(-1);
      return dt;
  }
  

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  Rector

  2020-05-18 回答