Recently, there is a demand for statistical distribution. It is necessary to count the distribution trend of this week, last week, this month, last month, this quarter, last quarter, this year, and last year, so it involves calculating weeks, months, and quarters. , the start and end times of the year, etc., the following summarizes the method of obtaining the start and end times of the week, month, quarter, year and other time periods according to the current time in C#. Not much nonsense, just paste the code directly, if you find it useful, please feel free recommend.
DateTime dt = DateTime.Now; //current time
DateTime startWeek = dt.AddDays(1 - Convert.ToInt32(dt.DayOfWeek.ToString("d"))); //Monday this week
DateTime endWeek = startWeek.AddDays(6); //This week Sunday
DateTime startMonth = dt.AddDays(1 - dt.Day); //The beginning of the month
DateTime endMonth = startMonth.AddMonths(1).AddDays(-1); //end of this month//
endMonth = startMonth.AddDays((dt.AddMonths(1) - dt).Days - 1); //end of this month
DateTime startQuarter = dt.AddMonths(0 - (dt.Month - 1) % 3).AddDays(1 - dt.Day); //beginning of the quarter
DateTime endQuarter = startQuarter.AddMonths(3).AddDays(-1); //end of the quarter
DateTime startYear = new DateTime(dt.Year, 1, 1); //beginning of the year
DateTime endYear = new DateTime(dt.Year, 12, 31); //At the end of this year, as for yesterday, tomorrow, last week, last month, last quarter, last year, etc.,
var Last Monday = DateTime.Now.AddDays(Convert.ToInt32(1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) - 7); //Last Monday
var last weekend = DateTime.Now.AddDays(Convert.ToInt32(1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) - 7).AddDays(6); // last weekend (Sunday) // next week
var next Monday = DateTime.Now.AddDays(Convert.ToInt32(1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) + 7); //Next Monday
var next weekend = DateTime.Now.AddDays(Convert.ToInt32(1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) + 7).AddDays(6); // next weekend
DateTime.Parse(DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() + "1").AddMonths(1).AddDays(-1).ToShortDateString();//最后一天
//It is easier to use the character formatting of ToString in C#
DateTime.Now.ToString("yyyy-MM-01");//本月初
DateTime.Parse(DateTime.Now.ToString("yyyy-MM-01")).AddMonths(1).AddDays(-1).ToShortDateString();//The last day of the month
DateTime.Parse(DateTime.Now.ToString("yyyy-MM-01")).AddMonths(-1).ToShortDateString();//The 1st of last month
DateTime.Parse(DateTime.Now.ToString("yyyy-MM-01")).AddDays(-1).ToShortDateString();//Last day of last month
DateTime.Parse(DateTime.Now.ToString("yyyy-MM-01")).AddMonths(1).ToShortDateString();// 下个月1号
DateTime.Parse(DateTime.Now.ToString("yyyy-MM-01")).AddMonths(2).AddDays(-1).ToShortDateString();//The last day of the next month
DateTime.Now.AddDays(7).ToShortDateString();//7天后
DateTime.Now.AddDays(-7).ToShortDateString();//7天前
DateTime.Now.Date.ToShortDateString();//This year, we can easily calculate the first and last day of the year by formatting the characters of ToString
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).ToShortDateString();//The first day of the year
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).AddYears(1).AddDays(-1).ToShortDateString();//The last day of the year
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).AddYears(-1).ToShortDateString(); //The first day of the previous year,
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).AddDays(-1).ToShortDateString();//The last day of the previous year,
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).AddYears(1).ToShortDateString(); //The first day of the next year
DateTime.Parse(DateTime.Now.ToString("yyyy-01-01")).AddYears(2).AddDays(-1).ToShortDateString();//The last day of the next year
// this quarter,
DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).AddDays(1 - DateTime.Now.Day);//The first day of the quarter;
DateTime.Parse(DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString("yyyy-MM-01")).AddDays(-1).ToShortDateString();/ /last day of the quarter
DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString("yyyy-MM-01");//The first day of the next quarter
DateTime.Parse(DateTime.Now.AddMonths(6 - ((DateTime.Now.Month - 1) % 3)).ToString("yyyy-MM-01")).AddDays(-1).ToShortDateString();/ / last day of next quarter
DateTime.Now.AddMonths(-3 - ((DateTime.Now.Month - 1) % 3)).AddDays(1 - DateTime.Now.Day);// 上季度第一天
DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).AddDays(1 - DateTime.Now.Day).AddDays(-1).ToShortDateString();// 上季度最后一天