I have a bunch of csv files I would like to rename with powershell.
from
abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-17-Oct-2018_23-49-38-6d73395f476ad09a7506dc00533933b8.csv
abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-15-Oct-2018_05-20-36-75eabae7c4123198ff5fe6f4f642449f.csv
abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-12-Oct-2018_06-23-58-b13eb8f362c09fbe405458fac8af8f8e.csv
to
abc-17-Oct-2018.csv
abc-15-Oct-2018.csv
abc-12-Oct-2018.csv
I could delete the characters after the underscore (_) with this command
Get-ChildItem -Filter *.csv | Foreach-Object -Process {
$NewName = [Regex]::Match($_.Name,"^[^_]*").Value + '.csv'
$_ | Rename-Item -NewName $NewName}
which leads me to this file name
abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-17-Oct-2018.csv
but I am lost at deleting the range of characters from the first hyphen to the third from last hyphen.
I tried this but get an error.
Get-ChildItem -Filter *.csv | Rename-Item -NewName {
-replace '^[^-]..^[^-]{-3}','^[^-]'}
Could somebody kindly enlighten me how to erase a range? (and possibly combine the former command)
Assuming that all input filenames have the same number of tokens with the same separators in the same positions:
Get-ChildItem -Filter *.csv | Rename-Item -NewName {
(($_.Name -split '[-_]')[0, 10, 11, 12] -join '-') + '.csv'
} -WhatIf
-WhatIf previews the renaming operations; remove it to perform actual renaming.
Splitting the filename into tokens by separators avoids complex regexes; PowerShell's flexible array slicing makes it easy to piece together the target filename from the tokens of interest accessed by their indices.
That said, if you wanted to do it with -replace and a complex regex:
Get-ChildItem -Filter *.csv | Rename-Item -NewName {
$_.Name -replace '^([^-]+).*?-(\d[^_]+).*', '$1-$2.csv'
} -Whatif
This solution doesn't assume a fixed position of the 2nd token to extract - the one before _ - and instead identifies its start by a - followed by a digit (\d).