Setting a variable in batch using powershell - powershell

Question

I have been racking my brain trying to figure this out.
this code
#echo off
powershell $Yesterday = (get-date((get-date).addDays(-1)) -format yyyyMMdd)
echo %Yesterday%
::neither one of these echo anything
#echo off
powershell Set-Variable -Name "Yesterday" -Value (get-date((get-date).addDays(-1)) -format yyyyMMdd)
echo %Yesterday%
should both return a response with yesterdays date (formatted as yyyMMdd), however, they do not. Using powershell, the following code does indeed work and return the correct response:
$Yesterday = (get-date((get-date).addDays(-1)) -format yyyyMMdd)
Write-Host $Yesterday
::Both of these work in powershell
Set-Variable -Name "Yesterday" -Value (get-date((get-date).addDays(-1)) -format yyyyMMdd)
Write-Host $Yesterday
however it does not work when used in batch. Any ideas why? I am trying to set the variable %Yesterday% in order to use it later in the script, but its not behaving itself as I expected. I'm sure its something simple, but I'm not seeing what it is right now.
similar question

Answer 1

This what you should use as code to set variable using Powershell and Batch
#echo off & color 0A
Title Setting a variable in batch using powershell
Set psCmd="get-date((get-date).addDays(-1)) -format yyyyMMdd"
Call :RunPS %psCmd% YesterDay
Echo YesterDay was %YesterDay%
pause & Exit
::----------------------------------------------------------------------
:RunPS <PassPSCMD> <Return value to be set as variable>
for /F "usebackq tokens=*" %%i in (`Powershell %1`) do set "%2=%%i"
Goto:eof
:: End of :RunPS function
::----------------------------------------------------------------------

Answer 2

Here is a one liner that will provide a var for yesterday's date in your batch script. The second line cleans up the temp file used to create the variable.
powershell -command "((Get-date).AddDays(-1)).ToString('yyyyMMdd')">captureVar && set /p Yesterday=<captureVar
if exist captureVar del captureVar
Line 1 starts out by instructing the cmd line to use PowerShell for the commands contained within the double quotes.
powershell -command "the powershell command(s)"
As it's name implies, the first PowerShell cmdlet will perform a function to Get-Date. Then, AddDays is used to change the date from the current value. A negative number will subtract and a positive number will add.
The default format looks like Friday, December 20, 2019 6:18:29 PM
To change the format, you must change the date into a string with format instructions
.ToString('dddd MM/dd/yyyy HH:mm:ss.ffff K')
The output of the PowerShell command is redirected into a file named captureVar. Another option would have been to have PowerShell write it to a file.
powershell -command "((Get-date).AddDays(-1)).ToString('yyyyMMdd') | set-content 'captureVar'" && set /p Today=<captureVar
I used && to make it a one liner. But you can set the var anytime after value has been written to the file.
set /p Today=<captureVar
The next line cleans up the temp file used to help create the var.

Answer 3

Defne the variable in batch, retrieve from Powershell
#echo off
%Yesterday% = powershell -command (get-date((get-date).addDays(-1)) -format yyyyMMdd)
echo %Yesterday%
pause