Powershell replacing periods - powershell

Can anyone tell me if they think there is something wrong with this Powershell script.
Dir |
where {$_.extension -eq ".txt"} |
Rename-Item –NewName { $_.name –replace “.“,”-” }
For each text file in the current directory, I'm trying to replace all periods in the file names with hyphens. Thanks ahead of time.

As the others have said, -replace uses regex (and "." is a special character in regex). However, their solutions are forgetting about the fileextension and they are acutally removing it. ex. "test.txt" becomes "test-txt" (no extension). A better solution would be:
dir -Filter *.txt | Rename-Item -NewName { $_.BaseName.replace(".","-") + $_.Extension }
This also uses -Filter to pick out only files ending with ".txt" which is faster then comparing with where.

-replace operates on regex, you need to escape '.':
rename-item -NewName { $_.Name -replace '\.', '-' }
Otherwise you will end up with '----' name...

The name property of a file object in powershell is of type string.
That means, you could also use the static string method replace like follows and don't care about regex' reserved characters:
dir | ? { $_.extension -eq ".txt" } | rename-item -newname { $_.name.replace(".","-") }

Related

How to add a symbol in a middle of a file name in PS

I have modified several thousand files with a various things requested by the owners.
Now, I need to add one final thing and I am not 100% on how to do it.
Scenario is as follows - all files have a 10 digit number at the start, I need to add a hyphen after the number. String is a variable but it is always the same length.
1234567890abcdefgh.xls would be an example
I have used GCI to make changes to symbols and static parts but not sure how to call for insertion in a specific place of a file (after the 10th character of a variable string)
Any ideas would be most welcome!
You can use the $matches you get from the capturing groups of a -match comparison:
(Get-ChildItem -Path 'X:\WhereTheFilesAre' -File) |
Where-Object { $_.BaseName -match '^(\d{10})([^-].*)' } |
Rename-Item -NewName { '{0}-{1}{2}' -f $matches[1], $matches[2], $_.Extension }
or by using the Substring() method:
(Get-ChildItem -Path 'X:\WhereTheFilesAre' -File) |
Where-Object { $_.BaseName -match '^\d{10}[^-]' } |
Rename-Item -NewName { $_.Name.Substring(0,10) + '-' + $_.Name.Substring(10) }
or use the regex -replace operator:
(Get-ChildItem -Path 'X:\WhereTheFilesAre' -File) |
Where-Object { $_.BaseName -match '^\d{10}[^-]' } |
Rename-Item -NewName { $_.Name -replace '^(\d{10})', '$1-' }
You can use string.Insert() to insert a string into another at a specific offset:
PS ~> '1234567890abcdefgh.xls'.Insert(10, '-')
1234567890-abcdefgh.xls
To apply to all files in a directory, you could do something like this:
Get-ChildItem -File |Where-Object Name -match '^\d{10}[^-]' |Rename-Item -NewName { $_.Name.Insert(10, '-') }
The regular expression pattern ^\d{10}[^-] will only match file names that start with 10 digits followed by something other than a hyphen (to avoid renaming files that already comply with the naming convention)

How can I use powershell to rename files with padded zeros

I need to limit the files affected to Example*.pdf. The files have 1-3 digits in the names and I need to standardize them. So Example_1.pdf -> Example_001.pdf while Example_100.pdf -> Example_100.pdf
The first part renamed files to Example.1.pdf so I could parse them with a single delimiter, but it gave me errors on the second step (cmdlet rename-item at command pipeline position 1 supply values for the following parameters: path)
Get-ChildItem of* | rename-item -newname { $_.Name -replace '_','.' }
Get-ChildItem of* |
foreach {
$nameArray = $_.Split('.')
$ExampleNumber = $nameArray[1]
rename-item -path $Path -newname $nameArray[0]+$ExampleNumber+$nameArray[2]
}
But if I can get something like this to work then I can play around with $ExampleNumber
Then I tried using regular expressions. Had this worked it would have padded the single digit files and then I could make a second pass for double digit files. But it didn't rename anything.
Get-ChildItem ex* | rename-item -newname { $_ -replace '(.*)(\d{1})\.pdf', 'Example_0$2.pdf'}
Any help is appreciated.
Note the $_ inside the -NewName block is of type FileInfo.
Here's my suggestion:
Get-ChildItem ex* | Rename-Item -NewName {
[void]($_.Name -match "\d+")
$_.Name -replace "\d+", (([int]$Matches[0]).ToString("000"))
}
Or alternatively:
Get-ChildItem ex* |
Rename-Item -NewName {
$_.Name -replace "\d+", (([int][regex]::match($_.Name, "\d+").value).ToString("000"))}

How do I remove periods from file names using PowerShell?

I'm trying to write a script in PowerShell that searches folders for files containing unnecessary periods, then mass removes the periods from the file names.
ex. Example.File.doc ---> ExampleFile.doc
Whenever I run the code, the console returns the following: "Rename-Item : Cannot bind argument to parameter 'NewName' because it is an empty string."
Does anyone know what the issue is?
Thanks in advance for any help!
$files = get-childitem -path "C:\XXXX\XXXX\XXXX" -Recurse
foreach($file in $files) {
if($file.Name -match ".") {
$newName = $file.Name -ireplace (".", "")
Rename-Item $file.FullName $newName
Write-Host "Renamed" $file.Name "to $newName at Location:" $file.FullName
}
}
One thing about string replacing: When I tried your example without escaping the period, it didn't replace anything and returned nothing (empty string), which I believe answers your "Cannot bind argument to parameter 'NewName' because it is an empty string"
This worked by escaping the period. Also, it works with or without the parenthesis.
$string = "the.file.name"
$newstring = $string -ireplace "\.", ""
// output: thefilename
$newstring.length
// output: 11
$othernewstring = $string -ireplace ("\.", "")
// output: thefilename
$othernewstring.length
// output: 11
// What the OP tried
$donothingstring = $string -ireplace (".", "")
// output:
$donothingstring.length
// output: 0
There is some additional information on string replace here, just for reference https://vexx32.github.io/2019/03/20/PowerShell-Replace-Operator/
$file.Name -ireplace (".", "")
invariably returns an empty string, because the -replace operator (-ireplace is just an alias[1]) operates on regexes (regular expressions), in which metacharacter . matches any character[2].
Since -replace always replaces all matches it finds, all characters in the input are replaced with the empty string, yielding an empty string overall, and passing an empty string via $newName to the (positionally implied) -NewName parameter of Rename-Item predictably causes the error message you saw.
To match a . character verbatim in a regex, you must escape it as \.:
$file.Name -replace '\.', '' # Note: no (...) needed; `, ''` optional
Note that it's generally better to use '...' quoting rather than "..." for regexes and string literals meant to be used verbatim.
However:
This would also remove the . char. in the filename extension, which is undesired.
Also, your command can be streamlined and simplified, as the solution below shows.
A concise, single-pipeline solution:
Get-ChildItem -File -Path "C:\XXXX\XXXX\XXXX" -Recurse -Include *.*.* |
Rename-Item -NewName { ($_.BaseName -replace '\.') + $_.Extension } -WhatIf
Note: The -WhatIf common parameter in the command above previews the operation. Remove -WhatIf once you're sure the operation will do what you want.
-File limits matching to files (not also directories).
-Include *.*.* limits matching to file names that contain at least 2 . chars.
Piping the files to rename directly from Get-ChildItem to Rename-Item allows you to specify the -NewName argument as a delay-bind script block ({ ... }), which can dynamically derive the new name from the name of the respective input file, using the properties of the System.IO.FileInfo instances received from Get-ChildItem.
$_.BaseName -replace '\.' removes all literal . chars. (escaped as \. in the context of the regex (regular expression) that the -replace operator operates on) from the file base name (the part without the (last) filename extension).
Note: not specifying a replacement operand is the same as specifying '', the empty string, resulting in the effective removal of the matched string; in other words: ... -replace '\.' is the same as ... -replace '\.', ''
+ $_.Extension appends the original extension to the modified base name.
[1] -replace is case-insensitive by default, as all PowerShell operators are; -ireplace just makes that fact explicit; there's also the -creplace variant, where the c indicates that the operation is case-sensitive.
[2] in single-line strings; in multi-line strings, . by default doesn't match \n (newlines), though this can be changed via inline matching option (?s) at the start of the regex.
There are a few other issues here. You should filter your Get-ChildItem results to return only files by including the -File switch.
Your current script will replace the last . before your file's extension which will cause some problems. You need to use the $File.BaseName and $File.Extension attributes to address this problem.
Substitute -ireplace with the .replace() method.
Lastly, you need to use the -like condition in your If statement. The -match condition is used for regexes and will not work correctly here.
$files = get-childitem -Recurse -File
foreach($file in $files) {
if($file.BaseName -like "*.*") {
$newName = $file.BaseName.Replace(".","") + $file.Extension
Rename-Item $file.FullName $newName
Write-Host "Renamed" $file.Name "to $newName at Location:" $file.FullName
}
}
Here's another solution that takes advantage of PowerShell's pipeline (remove the -WhatIf after you've tested which files will be renamed).
It also uses a lookahead regular expression to replace all but the last dot in the filename.
Get-ChildItem -Recurse `
<# Only select files that have more than one '.' in their name #> `
| Where-Object { ($_.Name.ToCharArray() | Where-Object {$_ -eq '.'} | Measure-Object ).Count -gt 1 } `
`
<# Change the location to the directory and rename so you don't have deal with the directory name #> `
<# Also, use a lookahead regex to replace all but the last dot. #> `
| ForEach-Object { Push-Location $_.Directory; Rename-Item $_ ($_.Name -replace "\.(?=.*?\.)", "") -Verbose -WhatIf; Pop-Location }
Here's a more concise version of the same commands using aliases:
dir -r | ?{ ($_.Name.ToCharArray() | ?{ $_ -eq '.' } | measure ).Count -gt 1 } | %{ pushd $_.Directory; ren $_ ($_.Name -replace "\.(?=.*?\.)", "") -v -wh; popd }

Renaming files with powershell to remove a string

I have a bunch of files with the same string in them and would like to remove them
Dir | Rename-Item -NewName { $_.Name -replace " (my string here)","" }
However, this does not seem to be removing the string from all the files that have that string in the file name. Do I need ReGex?
There is a space before the ( which makes me think I need ReGex in some way.
So I was right about needing ReGex with how Powershell does stuff:
Dir | Rename-Item -NewName { $_.Name -replace "(\s*) \(STRING HERE\)","" }
-replace does indeed use regex(case-insensitive).
You can achieve the same result without regex with the use of the .replace which is a string method like so:
Get-ChildItem -path 'your path' |
Rename-Item -NewName { $_.BaseName.replace(' (my string here)','') + $_.extension } -WhatIf
notice the use of $_.basename instead of name. this is because name consists of both filename and extension whereas basename does not.

Remove nth character from filename in PowerShell

I have a large number of files in a number of directories with this type of naming convention:
"BU1_KCG_RANDOM_030515.csv", etc.
I need to remove the 16th and 17th characters. So the new file name would be "BU1_KCG_RANDOM_0515.csv".
How can I iterate the multiple directory renaming accordingly?
So far I have got the below, but I am not sure what would come next.
Get-ChildItem -Filter *.csv -Recurse | Rename-Item -NewName {$_.Name..................}
Using -replace:
Get-ChildItem -Filter *.csv -Recurse |
foreach { $_ | rename-item -newname ($_.Name -replace '(.{15})..(.+)','$1$2') }
I much prefer mjolinor's answer, but you can always do things in a different way with PowerShell. Since you can index a string like a char array we can use a little array notation to get the characters you want as well.
$oldname = "BU1_KCG_RANDOM_030515.csv"
$newname = -join $oldname[0..14 + 17..($oldname.Length)]
$newname
BU1_KCG_RANDOM_0515.csv
We also need to use -join to convert the array back into a string.
Bit basic, eg doesn't check if the file has already been renamed, but should get you to the next step
gci -filter *.csv -rec | % { Rename-Item $_ -newname ($_.Name.substring(0,15) + $_.Name.substring(17)) }
where
gci = get-childitem
% = for-each
$_ = this (inside the for-each)