functions/Register-FileType.ps1
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function Register-FileType { <# .SYNOPSIS Registers a filetype with the parsing instructions to detect it. .DESCRIPTION Registers a filetype with the parsing instructions to detect it. The list populated with this data is used to verify, whether a file is of a specified type. .PARAMETER Type The type / file extension of the file type. .PARAMETER Mime The mime label files of that type have. .PARAMETER Bytes The byte-pattern to use to compare files with. Use $null as a wildcard entry that may be anything. .PARAMETER Offset The offset from where to start looking for the signature, verifying that the file is indeed of this type. Basically, the offset means "how many bytes, starting from the beginning of the file, to skip". .PARAMETER Description A description for the defined filetype. This could be general background or some important piece of extra documentation. .EXAMPLE PS C:\> Register-FileType -Type 'mp3' -Mime 'audio/mpeg' -Offset 0 -Bytes 73, 68, 51 Registers the mp3 file type. #> [CmdletBinding()] param ( [Parameter(Mandatory = $true, ValueFromPipelineByPropertyName = $true)] [AllowEmptyString()] [Alias('Extension')] [string[]] $Type, [Parameter(Mandatory = $true, ValueFromPipelineByPropertyName = $true)] [AllowEmptyString()] [string] $Mime, [Parameter(Mandatory = $true, ValueFromPipelineByPropertyName = $true)] [AllowEmptyCollection()] [AllowNull()] [Nullable[Byte][]] $Bytes, [Parameter(ValueFromPipelineByPropertyName = $true)] [int] $Offset, [Parameter(ValueFromPipelineByPropertyName = $true)] [AllowEmptyString()] [string] $Description ) process { if ($null -eq $Bytes) { $Bytes = @() } foreach ($typeName in $Type) { foreach ($typeElement in $typeName.Split(",")) { $fileType = New-Object FileType.FileType($Bytes, $typeElement.Trim("."), $Mime, $Offset, $Description) [FileType.FTHost]::FileTypes.Add($fileType) if (($Bytes.Length + $Offset) -gt ([FileType.FTHost]::MaxHeader)) { [FileType.FTHost]::MaxHeader = $Bytes.Length + $Offset } } } } } |