如何用C#和SQL获得当前月的第一天和最后一天 在日常开发中,经常需要我们对时间判断是否是在当前月内 C# int year = DateTime.Now.Year; int month = DateTime.Now.Month; DateTime firstDayOfThisMonth = new DateTime(year, month, 1); DateTime lastDayOfThisMonth = new DateTime(year, month, DateTime.DaysInMonth(year, month)); SQL DECLARE @NOW DATETIME DECLARE @FistDayOfThisMonth DATETIME DECLARE @LastDayOfThisMonth DATETIME SET @NOW = GETDATE() SET @FistDayOfThisMonth = @NOW - DAY(@NOW) + 1 SET @LastDayOfThisMonth = DATEADD(MONTH, 1, @NOW - DAY(@NOW) + 1) - 1 SELECT @FistDayOfThisMonth SELECT @LastDayOfThisMonth