Errors when calling powershell commands from cmd

Question

I'm trying to return value to my batch script. In powershell this script works fine:

PS> (Get-Date -Date "9.04.2017" -Uformat "%w.%Y-%m-%d").Replace("0.", "7.")
7.2017-04-09

When i try from batch:

for /f %%a in ('powershell ^(Get-Date -Uformat "%%w.%%Y-%%m-%%d"^).Replace^(^'0.^', ^'7.^'^)') do set datestamp=%%a
echo %datestamp%

I get errors, but this script works fine:

for /f %%a in ('powershell ^(get-date^).DayOfWeek') do set weekday=%%a
for /f %%a in ('powershell Get-Date -Uformat "%%u.%weekday%.%%Y-%%m-%%d"') do set datestamp=%%a
echo %datestamp%

What am I doing wrong?

also : I can't think of any reason why you would try to do this from batch? — bluuf, Apr 10 '17 at 12:50
I have a big batch script, where I need only one powershell call. Maybe later I''rewrite the script to powershell. — Antiokh, Apr 10 '17 at 12:53

score 5 · Accepted Answer · answered Apr 10 '17 at 12:54

5

In order to avoid need of escaping single quotes use useback parameter.Put everything in double quotes to avoid need of escaping brackets (and mind that -UFormat also accepts single quotes for the format):

for /f "usebackq" %%a in (`"powershell (Get-Date -Uformat '%%w.%%Y-%%m-%%d').Replace('0.', '7.')"`) do set datestamp=%%a
echo %datestamp%

answered Apr 10 '17 at 12:54

npocmaka

55,367
18
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`usebackq` is a great idea, but I suggest wrapping only the (implied) `-Command` argument (the string containing the PowerShell commands) in `"..."`: `for /f "usebackq" %%a in (\`powershell -Command "(Get-Date -Uformat '%%w.%%Y-%%m-%%d').Replace('0.', '7.')"\`) do set datestamp=%%a`. If you need to _embed_ `"` chars. inside the command string, use `\""` in _Windows PowerShell_ (`powershell.exe`) or, more simply and robustly, `""` in _PowerShell [Core] 6+_ (`pwsh.exe`). – mklement0 Feb 29 '20 at 13:18

score 2 · Answer 2 · answered Apr 10 '17 at 12:55

2

I've found my mistake. I need to escape comma-character. Now it looks strange, but works.

for /f %%a in ('powershell ^(Get-Date  -Date "9.04.2017" -Uformat "%%w.%%Y-%%m-%%d"^).Replace^(^'0.^'^,^'7.^'^)') do set datestamp=%%a
echo %datestamp%

answered Apr 10 '17 at 12:55

Antiokh

73
8

2

comma is a standard delimiter in batch files as long as ``,``,`,`,`;` and `=` and needs to be escaped in for loops. – npocmaka Apr 10 '17 at 12:58
To rephrase @npocmaka's helpful comment: all the characters mentioned function as _argument separators_. – mklement0 Apr 10 '17 at 13:50

Errors when calling powershell commands from cmd

2 Answers2