为什么 PowerShell -Replace 在每行前面添加一个额外的空白？

Question

I have a strange issue with -Replace in PowerShell. This command output a list, filtered:

PS C:\> dism /image:pro /Get-ProvisionedAppxPackages | Select-String -Pattern 'Nome'

Nome visualizzato: Microsoft.BingWeather
Nome visualizzato: Microsoft.DesktopAppInstaller
Nome visualizzato: Microsoft.GetHelp
Nome visualizzato: Microsoft.Getstarted
Nome visualizzato: Microsoft.HEIFImageExtension
Nome visualizzato: Microsoft.Messaging
Nome visualizzato: Microsoft.Microsoft3DViewer
Nome visualizzato: Microsoft.MicrosoftOfficeHub
Nome visualizzato: Microsoft.MicrosoftSolitaireCollection
Nome visualizzato: Microsoft.MicrosoftStickyNotes
Nome visualizzato: Microsoft.MixedReality.Portal
Nome visualizzato: Microsoft.MSPaint

Output is quite clean (some empty lines, not show here).

When i try to add | % {$_ -Replace '[^:]+:',''} | % {$_ -Replace '[^:]+:',''} for replacing all following the : character, an extra space is added to the list, at the beginning of each line :

PS C:\> dism /image:pro /Get-ProvisionedAppxPackages | Select-String -Pattern 'Nome' | % {$_ -Replace '[^:]+:',''}
 Microsoft.BingWeather
 Microsoft.DesktopAppInstaller
 Microsoft.GetHelp
 Microsoft.Getstarted
 Microsoft.HEIFImageExtension
 Microsoft.Messaging
 Microsoft.Microsoft3DViewer
 Microsoft.MicrosoftOfficeHub
 Microsoft.MicrosoftSolitaireCollection
 Microsoft.MicrosoftStickyNotes
 Microsoft.MixedReality.Portal
 Microsoft.MSPaint

Why? I can easly fix with an extra | % {$_ -Replace '\s+',''} | % {$_ -Replace '\s+',''} , but I'd like to understand why it's happening.

Answer 1

My comment as answer:

The extra space you see is the space character directly behind the colon. Your regex is not filtering that space out, so it remains as the first character in the output.

Instead of | % {$_ -Replace '[^:]+:',''} | % {$_ -Replace '[^:]+:',''} , use | % {$_ -replace '^.+:\s*'} | % {$_ -replace '^.+:\s*'} to remove everything from the start up to and including the colon AND all possible extra space characters that folow that.