c# - Setting a DateTime to the first of the next month?

Question

If I have var olddate = DateTime.Parse('05/13/2012');

and I want to get var newdate = (the first of the month after olddate, 06/01/2012 in this case);

What would I code? I tried to set the month+1 but month has no setter.

Answer 1

尝试这个：

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's Kind.

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

Answer 3

You have to define the Month and Year rightly, and after set the 1ª day. Try this:

// 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 4

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 5

很多例子......选择你的位置;）

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()));