Renaming a range from files w/Powershell - from first to third from last hyphen

问题

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

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)

回答1:

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).

回答2:

So I found a very long and convoluted way to do it, but it works so it works.

# Adds files into an object
$CSV = Get-ChildItem "C:\temp\test\*.csv" 

# Create a loop to action each file in the object created above
Foreach($File in $CSV){
    # Splits each part of the filename using the hyphen
    $NewName = @($File.basename.Split('-'))
    # created a new name using each individual part of the split original name
    # Also replaced the underscore section
    $NewFileName = "$($NewName[0])"+"-"+"$($NewName[10])"+"-"+"$($NewName[11])"+"-"+"$($NewName[12] -replace '_.*')"+".csv"
    # Renames file
    Rename-Item $File $NewFileName
}

回答3:

How about extract only what you need for the rename. Meaning What I tested. RegEx to trap first 4, date, and last 4. How I tested this approach.

Clear-Host

Write-Host "`nCreate the the file set *********" -ForegroundColor Cyan

'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' | 
%{New-Item -Path 'D:\Temp' -Name $_ -ItemType File}

Write-Host "`nValidate the file set creation *********" -ForegroundColor Cyan

(Get-ChildItem -Path 'D:\Temp' -Filter 'abc*').FullName


Write-Host "`nRead the folder for the file set and rename based on regex to shorten the name *********" -ForegroundColor Cyan

Get-ChildItem -Path 'D:\Temp' -Filter 'abc*' | 
%{ Rename-Item -Path $_.FullName -NewName  ([regex]::Matches($_.Name,'^.{0,4}|\d{2}.*\-\d{4}|.{4}$').Value -join '')}


Write-Host "`nValidate the name change *********" -ForegroundColor Cyan

(Get-ChildItem -Path 'D:\Temp' -Filter 'abc*').FullName

# Results

Create the the file set *********


    Directory: D:\Temp


Mode                LastWriteTime         Length Name                                                                                                                                               
----                -------------         ------ ----                                                                                                                                               
-a----       10/18/2018   9:29 PM              0 abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-17-Oct-2018_23-49-38-6d73395f476ad09a7506dc00533933b8.csv                                            
-a----       10/18/2018   9:29 PM              0 abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-15-Oct-2018_05-20-36-75eabae7c4123198ff5fe6f4f642449f.csv                                            
-a----       10/18/2018   9:29 PM              0 abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-12-Oct-2018_06-23-58-b13eb8f362c09fbe405458fac8af8f8e.csv                                            

Validate the file set creation *********

D:\Temp\abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-12-Oct-2018_06-23-58-b13eb8f362c09fbe405458fac8af8f8e.csv
D:\Temp\abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-15-Oct-2018_05-20-36-75eabae7c4123198ff5fe6f4f642449f.csv
D:\Temp\abc-def-ghi-jkl-mno-pqr-ke-traffic-by-domains-17-Oct-2018_23-49-38-6d73395f476ad09a7506dc00533933b8.csv

Read the folder for the file set and rename based on regex to shorten the name *********

Validate the name change *********

D:\Temp\abc-12-Oct-2018.csv
D:\Temp\abc-15-Oct-2018.csv
D:\Temp\abc-17-Oct-2018.csv

来源：https://stackoverflow.com/questions/52884866/renaming-a-range-from-files-w-powershell-from-first-to-third-from-last-hyphen

标签

powershell

renaming