C#.Net Getting Last day of the Previous Month from current date

Question

A quick expression anyone please?

Answer 1

var now = DateTime.Now;    
var firstDayCurrentMonth = new DateTime(now.Year, now.Month, 1);

var lastDayLastMonth = firstDayCurrentMonth.AddDays(-1);

Answer 2

DateTime now = DateTime.Now;
DateTime lastDayOfLastMonth = now.Date.AddDays(-now.Day);

Answer 3

Try the DateTime.DaysInMonth(int year, int month) method

Here's an example:

DateTime oneMonthAgo = DateTime.Now.AddMonths(-1);
int days = DateTime.DaysInMonth(oneMonthAgo.Year, oneMonthAgo.Month);