.Net: DateTime String format

I'm trying to add a timestamp to a file. However the DateTime Format ToString() looks weird to me.

Here is my code:

Dim _timeStamp As String = Date.Now.ToString("dd_mm_yyyy")

but the value looks like this:

_timeStamp = "03_24_2009"

I checked my PC and the current date is correct. Shouldn't the value look like this: 03_03_2009?

From stackoverflow

• For 2-digit month number, use MM not mm. Captial M's refer to month, lowercase m's refer to minutes.

  Also, John Sheehan has a nice cheat-sheet for such things.

  John Sheehan : Handy cheat sheet: http://john-sheehan.com/blog/net-cheat-sheets/

• Try using MM for month. The .ToString is case-sensitive, and lowercase means minutes.

• use MM, mm is for minutes

• mm is minutes. You want MM for months.

• As others have said, "mm" means minutes and "MM" means months.

  I find these MSDN pages useful:

  • Custom Date and Time Format Strings
  • Standard Date and Time Format Strings
  • Custom Numeric Format Strings
  • Standard Numeric Format Strings

  There are also various cheat sheets available on the web. I know I've seen a few of them around, but I only remember my own DZone refcard which includes it (also on Scribd).

  EDIT: As mentioned in the comments, John Sheehan has one too. Given that they're all free, why not download everything you can find and keep the one you find most useful? :)

  John Sheehan : Jon, I've put those pages into a cheat sheet: http://john-sheehan.com/blog/net-cheat-sheets/

  Jon Skeet : @John: So have I, effectively - see the edit I was making when you commented :) I'll add your link too.

• I always get this right thanks to my mnemonic:

  Months are larger than minutes, "MM" is larger than "mm"