Class FileFormat

Represents a file format that can be used to validate that a file's content matches its declared extension.

Inheritance

object

FileFormat

Namespace: FulcrumFS

Assembly: FulcrumFS.Core.dll

Syntax

public abstract class FileFormat

Remarks

Each FileFormat represents one specific file format with a fixed set of extensions. The base library provides built-in singletons for common formats accessible via static properties (Jpeg, Png, Pdf, etc.).

Content-agnostic and text-based file formats can be created using the factory methods (AnyContent(params ReadOnlySpan<string>), TextAscii(params ReadOnlySpan<string>), TextUnicode(params ReadOnlySpan<string>), TextEncoding(Encoding, params ReadOnlySpan<string>)) where the caller specifies the applicable extensions.

Custom file formats can be created by deriving from FileFormat and implementing ValidateAsync(Stream, CancellationToken).

FileFormat is independent of the FulcrumFS repository infrastructure and can be used standalone — for example, to validate user uploads in a front-end application before sending them to a service that hosts a FulcrumFS repository.

Constructors

Name	Description
FileFormat()	Initializes a new instance of the FileFormat class.

Properties

Name	Description
Avi	Gets the AVI media file format. Extension: .avi.
Avif	Gets the AVIF image file format. Extension: .avif.
Bmp	Gets the BMP image file format. Extensions: .bmp (primary), .bm, .dip.
Doc	Gets the legacy Microsoft Word (DOC) file format. Extension: .doc. Validates the OLE Compound Document signature and verifies the contained document is a Word document by inspecting the directory entries for the 'WordDocument' stream.
Docx	Gets the DOCX (Office Open XML Word document) file format. Extension: .docx.
Epub	Gets the EPUB e-book file format. Extension: .epub.
Extensions	Gets the file extensions associated with this file format (including the leading dot, e.g., ".jpg").
Flac	Gets the FLAC audio file format. Extension: .flac.
Gif	Gets the GIF image file format. Extension: .gif.
Heic	Gets the HEIC image file format. Extension: .heic.
Heif	Gets the HEIF image file format. Extensions: .heif (primary), .heifs, .hif.
Jpeg	Gets the JPEG image file format. Extensions: .jpg (primary), .jpeg, .jfif.
M2ts	Gets the MPEG-TS (192-byte packet, Blu-ray style) media file format. Extensions: .m2ts (primary), .mts.
M4a	Gets the MPEG-4 audio (M4A) media file format. Extension: .m4a.
Mj2	Gets the Motion JPEG 2000 (MJ2) media file format. Extension: .mj2.
Mkv	Gets the Matroska (MKV) media file format. Extension: .mkv.
Mov	Gets the QuickTime (MOV) media file format. Extension: .mov.
Mp3	Gets the MP3 audio file format. Extension: .mp3.
Mp4	Gets the MP4 media file format. Extension: .mp4.
Mpeg	Gets the MPEG-PS media file format. Extensions: .mpg (primary), .mpeg.
Name	Gets the name of the file format (e.g., "JPEG", "PDF", "TextUnicode").
Odp	Gets the ODP (OpenDocument presentation) file format. Extension: .odp.
Ods	Gets the ODS (OpenDocument spreadsheet) file format. Extension: .ods.
Odt	Gets the ODT (OpenDocument text) file format. Extension: .odt.
Ogg	Gets the Ogg media file format. Extensions: .ogg (primary), .oga, .ogv, .opus.
Pdf	Gets the PDF document file format. Extension: .pdf.
Png	Gets the PNG image file format. Extensions: .png (primary), .apng.
Ppt	Gets the legacy Microsoft PowerPoint (PPT) file format. Extension: .ppt. Validates the OLE Compound Document signature and verifies the contained document is a PowerPoint presentation by inspecting the directory entries for the 'PowerPoint Document' stream.
Pptx	Gets the PPTX (Office Open XML presentation) file format. Extension: .pptx.
PrimaryExtension	Gets the primary file extension associated with this file format (including the leading dot). This is the first extension in Extensions and is the extension that files of this format are written with when added to a FulcrumFS repository.
Rtf	Gets the RTF document file format. Extension: .rtf.
Tg2	Gets the 3GPP2 (3G2) media file format. Extension: .3g2.
Tgp	Gets the 3GPP (3GP) media file format. Extension: .3gp.
Tiff	Gets the TIFF image file format. Extensions: .tif (primary), .tiff.
Ts	Gets the MPEG-TS (188-byte packet) media file format. Extension: .ts.
Wav	Gets the WAV audio file format. Extension: .wav.
WebM	Gets the WebM media file format. Extension: .webm.
WebP	Gets the WebP image file format. Extension: .webp.
Xls	Gets the legacy Microsoft Excel (XLS) file format. Extension: .xls. Validates the OLE Compound Document signature and verifies the contained document is an Excel workbook by inspecting the directory entries for the 'Workbook' or 'Book' stream.
Xlsx	Gets the XLSX (Office Open XML spreadsheet) file format. Extension: .xlsx.
Zip	Gets the ZIP archive file format. Extension: .zip.

Methods

Name	Description
AnyContent(params ReadOnlySpan<string>)	Creates a FileFormat that accepts any content for the specified extensions. No content validation is performed beyond ensuring the file's extension is one of the specified extensions.
TextAscii(params ReadOnlySpan<string>)	Creates a FileFormat that validates files are valid ASCII text for the specified extensions. All bytes in the file must be in the range [0, 127] (i.e. IsValid(ReadOnlySpan<byte>) must return true).
TextEncoding(Encoding, params ReadOnlySpan<string>)	Creates a FileFormat that validates files decode successfully using the specified Encoding, for the specified extensions.
TextUnicode(UnicodeEncodings, params ReadOnlySpan<string>)	Creates a FileFormat that validates files are valid Unicode text in one of the specified encodings, for the specified extensions.
TextUnicode(params ReadOnlySpan<string>)	Creates a FileFormat that validates files are valid Unicode text in any encoding supported by All, for the specified extensions.
ToString()	Returns a string that represents the current object.
ValidateAsync(Stream, CancellationToken)	Validates the content of the specified stream against this file format. The stream must be seekable and positioned at 0 at the start of this call.