loader.psm1
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# this dummy class is used to determine whether # a file has a bom encoding: class NullEncoder : System.Text.UTF8Encoding { } function Get-PsOneEncoding { <# .SYNOPSIS Gets Encoding for BOM and Non-BOM text files. .DESCRIPTION Returns the encoding of text files. For BOM-encoded files, the fast .NET methods are used, and confidence level is always 100%. For Non-BOM-encoded files, extensive heuristicts are applied, and confidence level varies depending on file content. Heuristics are calculated by a porting of the Mozilla Universal Charset Detector (https://github.com/errepi/ude) Important: this library is subject to the Mozilla Public License Version 1.1, alternatively licensed either under terms of GNU General Public License Version 2 or later, or GNU Lesser General Public License Version 2.1 or later. .PARAMETER Path Path to text file .PARAMETER BomOnly Returns information for BOM-encoded files only. .EXAMPLE Get-PsOneEncoding -Path c:\sometextfile.txt Returns the encoding of the text file specified .EXAMPLE Get-ChildItem -Path $home -Filter *.txt -Recurse | Get-PsOneEncoding Returns the encoding of any text file found anywhere in the current user profile. .NOTES Make sure you respect the license terms of the ported charset detector DLL. .LINK https://github.com/TobiasPSP/GetEncoding https://github.com/errepi/ude https://techblog.dorogin.com/changing-source-files-encoding-and-some-fun-with-powershell-df23bf8410ab #> param ( [Parameter(ValueFromPipeline,ValueFromPipelineByPropertyName,Mandatory)] [Alias('FullName')] [string] $Path, [switch] $BomOnly ) begin { # load charset detector dll: Add-Type -Path $PSScriptRoot\Ude.dll $cdet = [Ude.CharsetDetector]::new() $nullEncoder = [NullEncoder]::new() } process { # try and read the BOM encoding: # submit a dummy encoder class that is used if the encoding cannot be # determined from BOM. This way we know that additional heuristic # analysis is needed: $reader = [System.IO.StreamReader]::new($Path,$nullEncoder,$true) # must read the file at least once to get encoding: $null = $reader.Peek() $encoding = $reader.CurrentEncoding $reader.Close() $reader.Dispose() # if the encoding equals default encoding then there was no bom: $bom = $encoding -ne $nullEncoder $bodyname = $encoding.BodyName $confidence = 100 # if there was no bom and non-bom files were not excluded... if (($bom -eq $false) -and ($BomOnly.IsPresent -eq $false)) { # ...do a heuristic analysis based on file content: [System.IO.FileStream]$stream = [System.IO.File]::OpenRead($Path) $cdet.Feed($stream) $cdet.DataEnd() $bodyname = $cdet.Charset $confidence = [int]($cdet.Confidence * 100) # add a workaround for the awkward default encoding created # by Set-Content on Windows PowerShell: if ($confidence -eq 0 -and $bodyname -eq $null) { $confidence = 25 $bodyname = 'ANSI' } $stream.Close() $stream.Dispose() } # return findings as a custom object: if ($bom -or !$BomOnly.IsPresent) { [PSCustomObject]@{ BOM = $bom Encoding = $bodyName.ToUpper() Confidence = $confidence Path = $Path } } } } Set-Alias -Name Get-Encoding -Value Get-PsOneEncoding |