Loading Web‑Open‑Font (WOFF) files | .NET

Loading Web‑Open‑Font (WOFF) Files with Aspose.Font for .NET

What you need

Item	Description	Where to get
Aspose.Font for .NET	Core library that reads, writes and converts font files (including WOFF/WOFF2).	dotnet add package Aspose.Font or via the NuGet UI (https://www.nuget.org/packages/Aspose.Font).
Target framework	.NET Framework 4.x / .NET Core 3.x / .NET 5/6/7 – any platform supported by Aspose.Font.	No extra runtime required.
Namespace imports	csharp\nusing Aspose.Font;\nusing Aspose.Font.Sources;\nusing System.IO;\n

Tip: All API docs are at https://reference.aspose.com/font/net/.

Loading a WOFF file from the file system

Step‑by‑step

1. Locate the font file (e.g. C:\Fonts\MyWebFont.woff).
2. Create a FileSystemStreamSource that gives the library a stream to that file.
3. Wrap the stream source in a FontFileDefinition – specify the extension "woff" (the library uses this to pick the right parser).
4. Create a FontDefinition – pass the appropriate FontType (Woff) and the FontFileDefinition.
5. Open the font via Font.Open() – you obtain an object derived from Aspose.Font.Font (e.g. WoffFont).

using System;
using System.IO;
using Aspose.Font;
using Aspose.Font.Sources;

class LoadWoffExample
{
    static void Main()
    {
        // Path to the .woff file
        string woffPath = @"C:\Fonts\MyWebFont.woff";

        // Stream source that reads directly from the file system
        FileSystemStreamSource streamSrc = new FileSystemStreamSource(woffPath);

        // FontFileDefinition – we tell Aspose it is a “woff” file
        FontFileDefinition fileDef = new FontFileDefinition("woff", streamSrc);

        // FontDefinition – specify the font type (Woff)
        FontDefinition fontDef = new FontDefinition(FontType.WOFF, fileDef);

        // Load the font
        Font woffFont = Font.Open(fontDef);

        // woffFont now gives you access to glyphs, metrics, encoding, etc.
        Console.WriteLine($"Loaded font: {woffFont.GetType().Name}");
    }
}

Result: woffFont is an instance of Aspose.Font.Woff.WoffFont. You can now render text, inspect glyph metrics, or convert it to another format (TTF, SVG, …).

Alternative ways to load WOFF fonts

Loading from a byte array (e.g. when the font is embedded in a resource or downloaded over HTTP)

byte[] woffBytes = File.ReadAllBytes(@"C:\Fonts\MyWebFont.woff");

// ByteContentStreamSource wraps the byte[] as a readable stream
ByteContentStreamSource byteSrc = new ByteContentStreamSource(woffBytes);

// Create definition – note we still supply "woff" as extension
FontDefinition fd = new FontDefinition(FontType.WOFF,
                                      "woff",
                                      byteSrc);

Font woffFont = Font.Open(fd);

Loading directly from a stream without an intermediate FileDefinition

If you already have an open FileStream:

using (FileStream fs = File.OpenRead(@"C:\Fonts\MyWebFont.woff"))
{
    // Wrap the live FileStream in FileSystemStreamSource
    var streamSrc = new FileSystemStreamSource(fs);

    // Directly pass stream source + extension into FontDefinition
    var fd = new FontDefinition(FontType.WOFF, "woff", streamSrc);
    var woffFont = Font.Open(fd);
}

Both approaches use the same underlying classes, only the source of bytes changes (disk file vs memory vs custom stream).

After loading – what can you do?

• Render text – use Aspose.Font.Rendering subsystem or export glyph outlines.
• Read font metrics – e.g. ((WoffFont)woffFont).Metrics.
• Convert to another format – call font.Save("output.ttf"); after casting to the appropriate subclass or using the generic API.
• Subset / merge – combine several fonts into one collection.
• Extract licensing info – if present in the WOFF header.

All of these are demonstrated in the official examples repository:

📂 https://github.com/aspose-font/Aspose.Font-Documentation/tree/master/net-examples

Quick checklist (for documentation pages)

• ✅ Add NuGet badge: [![NuGet](https://img.shields.io/nuget/v/Aspose.Font.svg)](https://www.nuget.org/packages/Aspose.Font/)
• ✅ Include sample code block (as shown above) with proper syntax highlighting.
• ✅ Mention supported extensions table (copy from section 2 above).
• ✅ Link to API reference for:
  • Aspose.Font.Font.Open
  • Aspose.Font.Sources.FileSystemStreamSource
  • Aspose.Font.Sources.ByteContentStreamSource
  • Aspose.Font.FontFileDefinition
  • Aspose.Font.FontDefinition
• ✅ Provide “Further reading” links:
  • Getting started: https://docs.aspose.com/font/net/getting-started/
  • Full API reference: https://reference.aspose.com/font/net/
  • Free online demo: https://products.aspose.app/font/conversion
• ✅ Add troubleshooting tip: If you receive “Unsupported font format”, verify that you passed both FontType.WOFF and a "woff" extension.