How to split a string and get the nth substring in Windows Powershell command line?

A PowerShell-idiomatic solution is to use the unary form of the -splitoperator, which behaves as follows:

• Leading and trailing whitespace is ignored.
• Any nonempty run of whitespace - no matter how long - is treated as a single separator.

$id = (-split (quser /server:'ServerName' | Where-Object { $_ -match 'jdoe' }))[2]

^{Note: You'll probably want to make the -match operation more robust, such as with -match '\bjdoe\b'}

A simpler example:

-split '  one          two  three ' | ForEach-Object { "[$_]" }

Output (prints the resulting tokens enclosed in [...]):

[one]
[two]
[three]

Note that there are reasons to generally prefer the -split operator to the .Split() .NET string method, as discussed in this answer.

in my opinion, in Windows cmd, you can use the FOR /F command to split a string and get the nth token (substring). Below is an example:

Suppose you have the following string: "This is a test string" and you want to get the 3rd word (which is "a" in this case). You could do:

@echo off
setlocal enabledelayedexpansion
set str="This is a test string"
for /f "tokens=3 delims= " %%a in ("%str%") do set nth_word=%%a
echo !nth_word!

In this script, tokens=3 specifies to get the third word, delims= sets the delimiter to a space (which is the separator in this case), %%a is the variable that will hold the value of the third word, "%str%" is the string to split, set nth_word=%%a sets the value of %%a to the variable nth_word, and echo !nth_word! prints out the value of nth_word.