Command not working in bat script but works in CLI

Question

Powershell -Command "cat .\tmp.txt | %{$_ -replace '\D', ''}"

I'm trying to run the above command in a batch script. It works perfectly fine if I run it on command line but this shows up if I try and run it from the script:

    Expressions are only allowed as the first element of a pipeline.
    At line:1 char:39
+ cat .\tmp.txt | {$_ -replace '\D', ''} <<<<
    + CategoryInfo          : ParserError: (:) [], ParentContainsErrorRecordException
    + FullyQualifiedErrorId : ExpressionsMustBeFirstInPipeline

Answer 1

powershell /?

If you run the above command this help text will show

-Command
...
To write a string that runs a Windows PowerShell command, use the format:
    "& {<command>}"
where the quotation marks indicate a string and the invoke operator (&)
causes the command to be executed.

Therefore you need to make the following changes in your batch file

powershell -Command "&{ cat .\tmp.txt | ForEach-Object {$_ -replace '\D', ''} }"

(note the extra curly braces wrapped around your command and % being replaced with ForEach-Object)