Regex - replace

Hey all,

I am still finding my way with Regex, but i have hit a bit of a brick wall and need some help pushing through.

I have a PST uploader for office 365 and when a user uploads a pst file it is saved on the server as jon.doe@constoso.com_1.pst. Now through powershell i am attempting to remove the _1.pst (keep in mind the domain name might change and the number can increment up as more uploads from the same user are received).

So I have the following:

$Displayname = “jon.doe@constoso.com_1.pst”

$DisplayName -replace “(_[0-9]).pst$”

When i use the following, the _ and number are removed, but not the .pst isnt.

I think i am close, just missing something simple…

I would remove the brackets () and escape the dot with a backslash. You don’t really need the brackets to create a group in this case.

$DisplayName -replace “_[0-9].pst$”

And replace the double quotes with singles or escape the dollar-sign with a backtick.

$DisplayName -replace ‘_[0-9].pst$’

$DisplayName -replace “_[0-9].pst`$”

I agree with the improvements that Daniel mentioned. However, your regex does remove the .pst for me and it should for you. Can you post the regex in context of the surrounding code?

Thanks Daniel! it worked perfectly!

Out of curiosity, when do you use the () in regex?

Apologies for my delayed reply. I’ve been on the move quite a bit since September 6th without access to a PC.

() are used in regular expressions to define a capturing group to extract data. You can read more about capturing groups here:

PowerShell Example:

Awesome thanks for this. Ill check the links as well.

Appreciate you remembering and replying!