This is more of a "mental" note for me than anything else, but I would like to share it with everyone as well. The DateTime.ToString method has 2 overloads, one with no parameters and the other with a string parameter. I would like to talk about the second one (hence the title of this post). You can pass a custom format pattern as the parameter to show the date anyway you want. Here are some of the possible values:

Pattern Description Example
yyyy Full Year 2008
yy Year 08
MM Month 05
MMM Month May
dd Day 02
d Day 2
HH Hour Military Notation 21
h Hour 9
mm Minutes 59
ss Seconds 34
ffff Milliseconds 0589
zzz Zone -04:00
t Meridiem P
tt Full Meridiem PM

 

Of course you can combine any of these to form a pattern for example:

yyyyMMddHHmmssffff would yield something like 200805221122350587 and you would do so like this:

DateTime.Now.ToString("yyyyMMddHHmmssffff");

There are also some predefined patterns

Pattern Example
d 5/22/2008
D Thursday, May 22, 2008
f Thursday, May 22, 2008 11:22 AM
F Thursday, May 22, 2008 11:22:34 AM
g 5/22/2008 11:22 AM
G 5/22/2008 11:22:34 AM
m May 22
o 2008-05-22T11:22:34:04.0000000
R Thu, 22 May 2008 11:22:34 EST
s 2008-05-22T11:22:34
t 11:22 AM
T 11:22:34 AM
u 2008-05-22 11:22:04Z
U Thursday, May 22, 2008 11:22:34 AM
y May, 2008

Happy Programming!