How to compress a directory with the built in .net compression classes?

Question

Using the System.IO.Compression namespaces classes GZIPStream and DeflateStream I successfully can compress and decompress individual files. However, if I pass a directoryna

Answer 1

This compresses .\in contents to .\out.zip with Powershell and System.IO.Packaging.ZipPackage following the example here

$zipArchive = $pwd.path + "\out.zip"
[System.Reflection.Assembly]::Load("WindowsBase,Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35")
$ZipPackage=[System.IO.Packaging.ZipPackage]::Open($zipArchive, [System.IO.FileMode]"OpenOrCreate", [System.IO.FileAccess]"ReadWrite")
$in = gci .\in | select -expand fullName
[array]$files = $in -replace "C:","" -replace "\\","/"
ForEach ($file In $files) {
   $partName=New-Object System.Uri($file, [System.UriKind]"Relative")
   $part=$ZipPackage.CreatePart($partName, "application/zip", [System.IO.Packaging.CompressionOption]"Maximum")
   $bytes=[System.IO.File]::ReadAllBytes($file)
   $stream=$part.GetStream()
   $stream.Write($bytes, 0, $bytes.Length)
   $stream.Close()
                                                    }
$ZipPackage.Close()