将日期时间设置为下个月的第一天

Question

如果我有var olddate = DateTime.Parse('05/13/2012');

我想得到var newdate = (the first of the month after olddate, 06/01/2012 in this case);

我会编码什么？我尝试设置月份+1，但月份没有设置器。

Answer 1

试试这个：

olddate = olddate.AddMonths(1);
DateTime newDate = new DateTime(olddate.Year, olddate.Month, 1, 
    0, 0, 0, olddate.Kind);

Answer 2

这永远不会导致超出范围的错误，并且会保留DateTime的种类。

dt = dt.AddMonths(1.0);
dt = new DateTime(dt.Year, dt.Month, 1, 0, 0, 0, dt.Kind);

Answer 3

试试这个简单的单行：

var olddate = DateTime.Parse("05/13/2012");
var newdate = olddate.AddDays(-olddate.Day + 1).AddMonths(1);
// newdate == DateTime.Parse("06/01/2012")

Answer 4

您必须正确定义月份和年份，并在设置1ª天之后。试试这个：

// define the right month and year of next month.
var tempDate = oldDate.AddMonths(1);
// define the newDate with the nextmonth and set the day as the first day :)
var newDate = new DateTime(tempDate.Year, tempDate.Month, 1); //create 

Answer 5

很多例子...选择你的姿势;)

var olddate = DateTime.Parse("05/12/2012");
int currentDay = ((DateTime)olddate).Day;
//can always replace the while loop and just put a 1 for current day
while(currentDay != 1)
   currentDay--;
var newdate = (DateTime.Parse(olddate.AddMonths(1).Month.ToString() + "/" + currentDay.ToString() + "/" + olddate.AddMonths(1).Year.ToString()));