Find a specific content of a file with a regular expression in powershell

find_content_with_regex.ps1

cls

$path = 'd:\Git\sp'
$file = '*.csproj'
$regex = "^.*(?=Output).*\.dll</HintPath>"
Get-ChildItem -Path $path -Name $file -Recurse | where {(get-Content $_ | Select-String $regex)}

This regular expression finds all files that contains a reference that not contains 'ThirdPartyLibraries'

<HintPath>(?!.*?ThirdPartyLibraries.*$)