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
• HTML rendering -- emit fragment or full-page HTML with customizable templates
• Front matter support -- parse YAML and TOML front matter into typed dictionaries
• 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 = MarkdownDoc.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("Benchmark", "v2.4", "v3.0")
        .Row("Parse 10K lines", "48 ms", "21 ms")
        .Row("Render to HTML", "35 ms", "14 ms")
        .Row("Round-trip fidelity", "97%", "100%")
        .AlignNumericRight())
    .Code("powershell", "dotnet add package OfficeIMO.Markdown");

string markdown = doc.ToMarkdown();
string html = doc.ToHtmlFragment();

var parsed = MarkdownReader.Parse(
    markdown,
    MarkdownReaderOptions.CreateGitHubFlavoredMarkdownProfile());

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

Compatibility

OfficeIMO.Markdown runs on Windows, Linux, and macOS. It is one of the lower-risk packages in the repo for trimming- or AOT-sensitive deployments, but you should still validate your own publish configuration and runtime targets.

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