////// 计算本周起始日期(礼拜一的日期) /// /// 该周中任意一天 ///返回礼拜一日期,后面的具体时、分、秒和传入值相等 public static DateTime CalculateFirstDateOfWeek(DateTime someDate) { int i = someDate.DayOfWeek - DayOfWeek.Monday; if (i == -1) i = 6;// i值 > = 0 ,因为枚举原因,Sunday排在最前,此时Sunday-Monday=-1,必须+7=6。 TimeSpan ts = new TimeSpan(i, 0, 0, 0); return someDate.Subtract(ts); } /**/////// 计算本周结束日期(礼拜日的日期) /// /// 该周中任意一天 ///返回礼拜日日期,后面的具体时、分、秒和传入值相等 public static DateTime CalculateLastDateOfWeek(DateTime someDate) { int i = someDate.DayOfWeek - DayOfWeek.Sunday; if(i != 0) i = 7 - i;// 因为枚举原因,Sunday排在最前,相减间隔要被7减。 TimeSpan ts = new TimeSpan(i, 0, 0, 0); return someDate.Add(ts); } /**/////// 判断选择的日期是否是本周(根据系统当前时间决定的‘本周’比较而言) /// /// ///public static bool IsThisWeek(DateTime someDate) { //得到someDate对应的周一 DateTime someMon = CalculateFirstDateOfWeek(someDate); //得到本周一 DateTime nowMon = CalculateFirstDateOfWeek(DateTime.Now); TimeSpan ts = someMon - nowMon; if (ts.Days < 0) ts = -ts;//取正 if (ts.Days >= 7) { return false; } else { return true; } }