Get-Date

The Get-Date cmdlet is pretty nifty and gives you a lot of date/time formats you’d want to use in your script.

Like if you were to save files with a unique stamp, you’d want a date/time format like <year><month><day><hour><minute><second>

Here are some examples to achieve this goal, with outputs

Get-Date -Format s
2015-11-19T20:22:35

(Get-Date -Format s).Replace("-","").Replace(":","").Replace("T","")
20151119202235


"{0}{1}{2}{3}{4}{5}" -f (Get-Date).Year,(Get-Date).Month,(Get-Date).Day,(Get-Date).Hour,(Get-Date).Minute,(Get-Date).Second
20151119202235

$Date = Get-Date
"{0}{1}{2}{3}{4}{5}" -f $Date.Year,$Date.Month,$Date.Day,$Date.Hour,$Date.Minute,$Date.Second
20151119202235


Get-Date -Format yyyyMMddHHmmss
20151119202235

Get-Date -UFormat %Y%m%d%H%M%S
20151119202235

As you can see, all the given examples have the same output.

The first example doesn’t completely live up to the task as I described in my format, thus I need to remove several characters (by replacing them with a blank), which is the second example.

The third and fourth example will do a format-string and get all different get-date attributes. The fourth example is the same as the third, but in this case I fist put the output of the Get-Date cmdlet into a variable called $Date, this already makes the code a little bit less, but still longer than the Second example.

The fifth and sixth example use the formatting parameters Format and Uformat. Format is the .Net format and UFormat is the Unix format. Those are the shortest ones to use.

I myself like the switches for formatting a lot, for cases where you need to get the date the way you want it, without changing the localization settings of a server/computer.

Like for example in the EU, most (or maybe all) countries work with dates in the <day>-<month>-<year> pattern and time in the 24H format; while in the US dates are worked with in the <month>/<day>/<year> pattern and time in 12h format with AM and PM. But once working with files and sorting dates, the format as used in the example in usually used.

The PowerShell help tells us all the options for Uformat (each is preceded by a % sign):

• c Date and time – abbreviated (Fri Jun 16 10:31:27 2006)

Date:

• D Date in mm/dd/yy format (06/14/06)
• x Date in standard format for locale (09/12/07 for English-US)

Year:

• C Century (20 for 2006)
• Y Year in 4-digit format (2006)
• y Year in 2-digit format (06)
• G Same as ‘Y’
• g Same as ‘y’

Month:

• b Month name – abbreviated (Jan)
• B Month name – full (January)
• h Same as ‘b’
• m Month number (06)

Week:

• W Week of the year (00-52)
• V Week of the year (01-53)
• U Same as ‘W’

Day:

• a Day of the week – abbreviated name (Mon)
• A Day of the week – full name (Monday)
• u Day of the week – number (Monday = 1)
• d Day of the month – 2 digits (05)
• e Day of the month – digit preceded by a space ( 5)
• j Day of the year – (1-366)
• w Same as ‘u’

Time:

• p AM or PM
• r Time in 12-hour format (09:15:36 AM)
• R Time in 24-hour format – no seconds (17:45)
• T Time in 24 hour format (17:45:52)
• X Same as ‘T’
• Z Time zone offset from Universal Time Coordinate (UTC) (-07)

Hour:

• H Hour in 24-hour format (17)
• I Hour in 12 hour format (05)
• k Same as ‘H’
• l Same as ‘I’ (Upper-case I = Lower-case L)

Minutes & Seconds:

• M Minutes (35)
• S Seconds (05)
• s Seconds elapsed since January 1, 1970 00:00:00 (1150451174.95705)

Special Characters:

• n newline character (\n)
• t Tab character (\t)

The help tells us that the settings for the Format switch can be found here. This is the information which is currently (when writing this blog) available on the site:

The following table lists the custom DateTime format patterns and their behavior. For more information, see Custom DateTime Format Strings.