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@marcgeld
Last active April 11, 2023 09:11
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Powershell: Compress and decompress byte array
# Compress and decompress byte array
function Get-CompressedByteArray {
[CmdletBinding()]
Param (
[Parameter(Mandatory,ValueFromPipeline,ValueFromPipelineByPropertyName)]
[byte[]] $byteArray = $(Throw("-byteArray is required"))
)
Process {
Write-Verbose "Get-CompressedByteArray"
[System.IO.MemoryStream] $output = New-Object System.IO.MemoryStream
$gzipStream = New-Object System.IO.Compression.GzipStream $output, ([IO.Compression.CompressionMode]::Compress)
$gzipStream.Write( $byteArray, 0, $byteArray.Length )
$gzipStream.Close()
$output.Close()
$tmp = $output.ToArray()
Write-Output $tmp
}
}
function Get-DecompressedByteArray {
[CmdletBinding()]
Param (
[Parameter(Mandatory,ValueFromPipeline,ValueFromPipelineByPropertyName)]
[byte[]] $byteArray = $(Throw("-byteArray is required"))
)
Process {
Write-Verbose "Get-DecompressedByteArray"
$input = New-Object System.IO.MemoryStream( , $byteArray )
$output = New-Object System.IO.MemoryStream
$gzipStream = New-Object System.IO.Compression.GzipStream $input, ([IO.Compression.CompressionMode]::Decompress)
$gzipStream.CopyTo( $output )
$gzipStream.Close()
$input.Close()
[byte[]] $byteOutArray = $output.ToArray()
Write-Output $byteOutArray
}
}
[string] $text = "some text to encode"
Write-Host "Text: " ( $text | Out-String )
[System.Text.Encoding] $enc = [System.Text.Encoding]::UTF8
[byte[]] $encText = $enc.GetBytes( $text )
$compressedByteArray = Get-CompressedByteArray -byteArray $encText
Write-Host "Encoded: " ( $enc.GetString( $compressedByteArray ) | Out-String )
$decompressedByteArray = Get-DecompressedByteArray -byteArray $compressedByteArray
Write-Host "Decoded: " ( $enc.GetString( $decompressedByteArray ) | Out-String )
@rolambert
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Running this today I get:

New-Object : Cannot find an overload for "GZipStream" and the argument count: "2".
At line:11 char:23
+ ... zipStream = New-Object System.IO.Compression.GzipStream $output, ([IO ...
+                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [New-Object], MethodException
    + FullyQualifiedErrorId : ConstructorInvokedThrowException,Microsoft.PowerShell.Commands.NewObjectCommand

Though I actually see two overloads in the docs. How to fix this?

  • this removed the overload for me
$file = [System.IO.File]::ReadAllBytes("C:\temp\webcontrol\wc.gz.zip")

$im = New-Object System.IO.MemoryStream(,$file)

@JonathonFS
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JonathonFS commented Jan 12, 2023

Running this today I get:

New-Object : Cannot find an overload for "GZipStream" and the argument count: "2".
At line:11 char:23
+ ... zipStream = New-Object System.IO.Compression.GzipStream $output, ([IO ...
+                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [New-Object], MethodException
    + FullyQualifiedErrorId : ConstructorInvokedThrowException,Microsoft.PowerShell.Commands.NewObjectCommand

Though I actually see two overloads in the docs. How to fix this?

The $input variable is special and can cause weird behavior if you try to use it like a normal variable. This particular error is being caused because the $input variable is of type ArrayListEnumeratorSimple, but the method expects a MemoryStream variable. Just find an replace all instances of $input with another variable name, like $inStream.

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