How do I get a dattime format in C# that will look like this:

2011-09-01 00:00:00:000
This works
DateTime saveNow = DateTime.Now;

string test = String.Format("{0:yyyy-MM-01 00:00:00:000}", saveNow);

Now I want to know this. How would I subtract one month from the current month?

It T-SQL it would look like this

How would it be done in C#?

trying the addmonth method with a negative one did not work