Fixing Missing NuGet Packages

I have encountered this problem more than one time. Somehow, maybe when merging changes between branches, there are references in .NET projects to assemblies in NuGet packages that are not present in packages.config, which in turn can result in issues when updating packages to later versions. I put together a PowerShell script to detect this issues. It searches all .csproj files in subfolders to the current one.

# Get reference hintpath to packages:
$pattern = "<HintPath>.*Packages\\(?<id>(?:[a-zA-Z]+\.?)+)\.(?<version>(?:\d+\.)+\d+)\\.*</HintPath>"

Get-ChildItem -Path . -Filter "*.csproj" -File -Recurse | foreach {
    $projFilename = $_.FullName
    Write-Output "`r`n*** $projFilename ***"
    $packageFilename = "$($_.DirectoryName)\packages.config"
    if ([System.IO.File]::Exists($packageFilename))
    {
        $projtext = Get-Content -Path $projFilename
        $projtext | foreach {
            if ($_ -imatch $pattern)
            {
                $id = $Matches.Item("id")
                $version = $Matches.Item("version")
                Write-Output "$($Matches[0])"
                $foundInPackages = Select-String -Pattern "id=""$id"" version=""$version""" -Path $packageFilename -Quiet
                if ($foundInPackages) {
                    Write-Output (Select-String -Pattern "id=""$id"" version=""$version""" -Path $packageFilename).Line
                } else {
                    Write-Warning "Not found in package file!"
                }
            }
        }
    } else {
        Write-Warning "There is no package file at $packageFilename!"
    }
}