OfficeIMO.Markdown

Why OfficeIMO.Markdown?

OfficeIMO.Markdown is a purpose-built Markdown engine for .NET. It gives you a strongly typed AST, a fluent builder for document construction, and multiple reader profiles so you can parse CommonMark, GFM, or OfficeIMO-flavored Markdown with one library. Every node carries source span information, which makes it a practical fit for tooling, linters, and editor integrations.

Features

• Fluent document builder — construct Markdown documents programmatically with a chainable API
• Typed block & inline AST model — headings, paragraphs, lists, tables, code blocks, emphasis, links, and images as strongly typed objects
• Source spans for every node — line, column, and offset tracking for diagnostics and editor support
• Multiple reader profiles — OfficeIMO, CommonMark, GFM, and Portable profiles with configurable strictness; CommonMark 0.31.2: 652/652 spec examples
• HTML rendering — emit fragment or full-page HTML with customizable templates
• Front matter support — read, edit and write YAML front matter, including nested values, through OfficeIMO.Yaml without losing comments or formatting
• TOC helpers & callouts — generate table of contents from headings and render note/warning/tip callouts
• Tables from objects — build Markdown tables directly from collections with column selectors
• Input normalization presets — normalize line endings, whitespace, and encoding before parsing
• Post-parse document transforms — rewrite, filter, or augment the AST after parsing
• Extension API — register custom block and inline parsers for domain-specific syntax
• Zero external dependencies — ships as a single assembly with no third-party references

Quick start

using OfficeIMO.Markdown;

var doc = MarkdownDocument.Create()
    .FrontMatter(new { title = "Release Notes", tags = new[] { "docs", "release" } })
    .H1("Release Notes")
    .P("Version 3.0 introduces several improvements.")
    .H2("New Features")
    .Ul(ul => ul
        .Item("Fluent document builder")
        .Item("Typed AST and traversal helpers")
        .Item("HTML fragment and full-page rendering"))
    .H2("Performance")
    .Table(t => t
        .Headers("Package", "Change", "Owner")
        .Row("OfficeIMO.Markdown", "Typed AST traversal", "Documentation")
        .Row("OfficeIMO.Word.Markdown", "Word conversion", "Automation")
        .Row("OfficeIMO.Markdown.Html", "HTML conversion", "Web"))
    .Code("powershell", "dotnet add package OfficeIMO.Markdown");

string markdown = doc.ToMarkdown();
string html = doc.ToHtml(new MarkdownHtmlExportOptions { Kind = MarkdownHtmlKind.Fragment });

var parsed = MarkdownDocument.Parse(
    markdown,
    MarkdownLoadOptions.CreateGitHubFlavoredMarkdownProfile());

// Inspect the AST
foreach (var block in parsed.DescendantsAndSelf())
{
    Console.WriteLine(block.GetType().Name);
}

Compatibility

The CommonMark profile matches all 652 examples of the official CommonMark 0.31.2 specification, and the GFM profile passes all 52 tracked cmark-gfm extension fixtures. The compatibility matrix lists every extension family and its exact boundary.

OfficeIMO.Markdown runs on Windows, Linux, and macOS. Its checked-in NativeAOT smoke publishes and executes fluent composition and rendering; use the deployment guide to reproduce that baseline and then add the exact extensions your application needs.

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