Remove parentheses in powershell regex?

Question

I cant find a find an answer that is clear to me. I am changing a bunch of image file names in a directory, when I rename them they all get renamed to image (1).png image (2).png for as many images as I have then I run this in power shell.

Dir | Rename-Item –NewName { $_.name –replace " ","_" }

This finds the space and renames it to image_(1).png image_(2).png nice and easy, but It becomes a headache trying to replace the parentheses. I am trying to get rid of them to look like this image_1.png image_2.png but it's gotten really frustrating finding an answer lol.

I wish I could just write.

Dir | Rename-Item –NewName { $_.name –replace "\(*\)","*" } 

or

Dir | Rename-Item –NewName { $_.name –replace "\([1-10]\)","[1-10]" }

or

Dir | Rename-Item –NewName { $_.name –replace "\(\W\)","\W" }

I tried them all and you would think that syntax is valid, but nope :( So I am hoping for a little nudge in the right direction.

Solution 1

I don't have enough SO Rep to comment on your question so I have to try for an answer. Do you need to escape your backslashes? ie. Replace

"\(*\)","" with "\\(*\\)",""

Is your issue with the command syntax or the Regex itself? The raw Regex would look something like this:

^(?\<Name>.*)\((?<Number>\d*?)\)\.(?<Extension>.*$)

and replace with: ${Name}_${Number}.${Extension}

Solution 2

How about:

Dir | Rename-Item –NewName { $_.name.replace(' ','_') -replace '[()]','' }

The string .replace() method is much more efficient for single literal character replacement. Use the -replace operator for more complex operations where you need to specify multiple characters at once.

Solution 3

Couldn't comment under the answer but this is a way to getting rid of the "()" and the text inside in one go.

Rename-Item –NewName { $_.name -replace "(\(\d+\))",""}

The \( and \) escapes the parentheses making them literal parentheses. The non-escaped parentheses group the captured pattern to be referenced later and may not be needed here for what you are doing.

Hope this helps someone.

Comments

[Michael Joseph Aubry]

I need to remove them, having () in file names aren't really flexiable when using in css and stuff. I am not 100% what the issue is, I know some syntax's are valid but make no changes, and them some I tried like @EBGreen's answer give me an error saying cannot rename.

[Jon Upchurch]

I just updated my response to correct the formatting. The regex I posted will capture those and strip out the parens replacing them with the initial underscore. So: image (1).png becomes image _1.png

[Michael Joseph Aubry]

Okay I am trying it now, thanks so much for the answer.

[Jon Upchurch]

Sure. Bear in mind, it's possible you'll have to use double backslashes when using my solution. I don't know if powershell requires you to escape those characters in strings or not, but I'd assume you probably would.

[Michael Joseph Aubry]

nice this Dir | Rename-Item –NewName { $_.name –replace "\(*\)","" } removed one side of the parentheses file name looks like this image_(1.png almost there but not sure why it didnt remove both?

[Jon Upchurch]

If you're trying to use your original command, just put two backslashes everywhere you'd use one. If you're trying to use the regex I supplied, it would be something like: Dir | Rename-Item –NewName { $_.name –replace "^(?\<Name>.*)\((?<Number>\d*?)\)\.(?<Extension>.*$)", "${Name}_${Number}.${Extension}" } If that doesn't work you might also have to replace any single '\' with '\\'

[Michael Joseph Aubry]

ok thats what I am trying now to use // I need to rename the files should take a minuet be right back, thanks again.

[Michael Joseph Aubry]

It said this regex is not valid Dir | Rename-Item –NewName { $_.name –replace "^(?\<Name>.*)\((?<Number>\d*?)\)\.( ?<Extension>.*$)", "${Name}_${Number}.${Extension}" } The input to the script block for parameter 'NewName ((?<Number>\d*?))\.(?<Extension>.*$) is not valid.

[Michael Joseph Aubry]

Got it to work I did this first Dir | Rename-Item –NewName { $_.name –replace "\(*\)", "" } to remove ) then did Dir | Rename-Item –NewName { $_.name –replace "\(*\(", "" } to remove ( ... Thanks again, this was way more difficult than I would have liked..