Powershell Removing Leading Zero from File Name - powershell

Question

I have a folder with Several files from the that look like:
XXX_01_07_11_1.bat
XX_1_07_06_02.bat
XXXX_2_22_14_01_02.bat
Without a specific length.
I would like to rename all the files in the folder removing all the leading zeros.
for example XXX_01_07_11_1.bat will be renamed to XXX_1_7_11_1.bat .
I found some ways to do it in Bash but not with powershell.

Answer 1

Apply _0+(?=[1-9]) or _0+(?=\d) regex as follows:
Get-ChildItem . -File -Filter "*_0*.*" |
ForEach-Object {
Rename-Item $_.FullName $($_.Name -replace '_0+(?=\d)', '_') -WhatIf
}
Remove the risk mitigation parameter -WhatIf as soon as debugged (or use -WhatIf:$false to suppress the automatic WhatIf behaviour that results when the value of the $WhatIfPreference variable is 1, see also Get-Help about_Preference_Variables).
Regex explanation:
_ matches the character _ Low Line (underscore) literally
0+ matches the character 0 literally
+ Quantifier — Matches between one and unlimited times, as many times as possible, giving back as needed (greedy)
?= Positive Lookahead. Assert that above _0+ match is followed by
[1-9] a single character in the [1-9] list i.e. in the range between 1 (unicode 49) and 9 (unicode 57), or
\d a digit (equals to [0-9] list but [1-9] effectively due to greedy ´0+´ above).

Answer 2

The easiest way is replacing _0 to _, like this:
Get-ChildItem _my_Path | ForEach-Object {
$f_name = $_.FullName
$name = $_.Name
$new_name = $name -replace "_0","_"
Rename-Item $f_name -NewName $new_name
}
Please have a try. :)

Answer 3

try this:
get-childitem "c:\temp" -file -filter "*.bat" | %{
$NewName=($_.Name -split '_' | %{if ($_ -eq '0') {'0'} else {$_.TrimStart('0')}}) -join '_'
Rename-Item $_.FullName $NewName
}

Answer 4

Note: This is at heart similar to the accepted answer, but demonstrates that you can pipe Get-ChildItem output directly to Rename-Item, which is both more concise and more efficient.
Get-ChildItem . -Filter *.bat |
Rename-Item -NewName { $_.Name -replace '(?<=_)0+' } -WhatIf
Specify the desired target folder instead of .
-WhatIf previews the renaming; remove it to actually rename.
You can pass a script block ({ ... }) to Rename-Item -NewName, which is evaluated for each input object (file), and in which $_ refers to the file at hand.
Note that this works even though -NewName is a [string]-typed parameter. The ability to pass a script block instead - a script-block parameter is a powerful generic PowerShell feature that allows you to calculate the parameter value on a per-input-object basis via a script block - see here for details.
-replace performs regex-based string replacement and '(?<=_)0+' replaces any sequence of one or more (+) 0 chars., if preceded by (?<=) a _ char.
(?<=_) is an instance of a (positive) lookbehind assertion, which means that while the _ is matched, it won't be captured; that is, it doesn't become part of what is being replaced.
Since no replacement string is given, the zeros are effectively removed.

Answer 5

cd c:\temp
'X_01_00007_11_1.bat','X_1_07_06_02.bat','X_2_22_14_01_02.bat','X_000_0_07_06_02.bat'|% {
New-Item $_ -Force}
Get-ChildItem -Path C:\Temp -File |ForEach-Object {
$oldname=$_.Name
$newname = $oldname -replace '_0+(?=\d)', '_'
#or
#$newname = $oldname -replace '_0+(\d)', '_$1'
Rename-Item $oldname -NewName $newname
}
目录: C:\temp
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 2018/5/7 20:55 0 X_01_00007_11_1.bat
-a---- 2018/5/7 20:55 0 X_1_07_06_02.bat
-a---- 2018/5/7 20:55 0 X_2_22_14_01_02.bat
-a---- 2018/5/7 20:55 0 X_000_0_07_06_02.bat
PS C:\temp> dir
目录: C:\temp
Mode LastWriteTime Length Name
---- ------------- ------ ----
-a---- 2018/5/7 20:55 0 X_0_0_7_6_2.bat
-a---- 2018/5/7 20:55 0 X_1_7_11_1.bat
-a---- 2018/5/7 20:55 0 X_1_7_6_2.bat
-a---- 2018/5/7 20:55 0 X_2_22_14_1_2.bat