Get regex working in powershell script

Question

I'm trying to rename several files using a regex expression.

ck1823000-23.dat
ck1293834-67.dat
lo1230324-99.dat
pk1232131-34.dat
...

I want to remove -XX So the result would be like this:

ck1823000.dat
ck1293834.dat
lo1230324.dat
pk1232131.dat
...

I came up with this regex:

(?:.*?)([-\\s].*?).dat

But I get this error:

Rename-Item : The input to the script block for parameter 'NewName' failed. The regular expression pattern is not valid

When I run this command:

Get-ChildItem . -file -Filter "*.dat" | Rename-Item -newname { $_.name -replace "\(?:.*?)([-\\s].*?).dat\", ""}

Avinash Raj · Accepted Answer · 2014-10-02 09:16:36Z

1

Use the below regex and then replace the matched characters with an empty string.

-[^.-]*(?=\\.dat)

Get-ChildItem . -file -Filter "*.dat" | Rename-Item -newname { $_.name -replace "-[^.-]*(?=\\.dat)", ""}

answered Oct 2, 2014 at 9:00

Avinash Raj

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2 Comments

Thanks! Works great. So I guess I can't use groups to match

I think you can. REgex : ^(.*?)([-\\s].*?)(\\.dat)$ replacemet string: $1$3 DEmo regex101.com/r/qM2pT8/2

walid toumi · Accepted Answer · 2014-10-02 13:15:25Z

1

Another option you can use basename instead of name property

Get-ChildItem . -file -Filter "*.dat" | 
   Rename-Item -newname { $_.basename -replace "-.*"}

answered Oct 2, 2014 at 13:15

walid toumi

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