OfficeIMO.Reader.Html 3.0.3

OfficeIMO.Reader.Html - HTML reader adapter

OfficeIMO.Reader.Html provides a modular HTML and MHTML ingestion adapter for OfficeIMO.Reader.Core.

Install

dotnet add package OfficeIMO.Reader.Html

Configure

using OfficeIMO.Reader;
using OfficeIMO.Reader.Html;

OfficeDocumentReader reader = new OfficeDocumentReaderBuilder()
    .AddHtmlHandler()
    .Build();

The same registration handles .mht and .mhtml. Embedded MHTML resources become normal Reader assets and the archive uses the same rich HTML projection:

OfficeDocumentReadResult result = reader.ReadDocument("snapshot.mhtml");

foreach (OfficeDocumentAsset asset in result.Assets) {
    Console.WriteLine($"{asset.FileName}: {asset.LengthBytes}");
}

For untrusted or size-sensitive HTML:

OfficeDocumentReader reader = new OfficeDocumentReaderBuilder()
    .AddHtmlHandler(ReaderHtmlOptions.CreateUntrustedHtmlProfile(maxInputCharacters: 100_000))
    .Build();

ReaderHtmlOptions.ConversionOptions exposes the same trust, URL, and complexity policy used by other OfficeIMO.Html adapters. CreateUntrustedHtmlProfile applies its character cap both before shared parsing and during Markdown projection, so the reader does not maintain a second limit decision.

Examples

Convert HTML to Markdown chunks

using OfficeIMO.Reader;
using OfficeIMO.Reader.Html;

ReaderHtmlOptions htmlOptions = ReaderHtmlOptions.CreatePortableProfile();
htmlOptions.ChunkByHeadings = true;
OfficeDocumentReader reader = new OfficeDocumentReaderBuilder()
    .AddHtmlHandler(htmlOptions)
    .Build();

foreach (var chunk in reader.Read("page.html", new ReaderOptions {
    MaxChars = 5_000
})) {
    Console.WriteLine($"{chunk.Id}: {chunk.Location.HeadingPath}");
    Console.WriteLine(chunk.Markdown ?? chunk.Text);
}

Extract tables from HTML

using OfficeIMO.Reader;
using OfficeIMO.Reader.Html;

OfficeDocumentReader reader = new OfficeDocumentReaderBuilder()
    .AddHtmlHandler()
    .Build();

IReadOnlyList<ReaderTable> tables = reader.ReadTables("report.html",
    new ReaderOptions {
        MaxTableRows = 250
    });

foreach (var table in tables) {
    Console.WriteLine($"{table.Rows.Count} row(s), {table.ColumnProfiles.Count} column profile(s)");
}

Read the rich document result

OfficeDocumentReader reader = new OfficeDocumentReaderBuilder()
    .AddHtmlHandler()
    .Build();
OfficeDocumentReadResult document = reader.ReadDocument("application.html");

foreach (OfficeDocumentFormField field in document.Forms) {
    Console.WriteLine($"{field.Name}: {field.Value}");
}

foreach (OfficeDocumentLink link in document.Links) {
    Console.WriteLine(link.Uri ?? link.DestinationName);
}

reader.ReadDocument("application.html") dispatches to this native rich mapping.

What it emits

• HTML converted to Markdown through OfficeIMO.Markdown.Html.
• Markdown-shaped ReaderChunk output.
• Table extraction with ReaderTable.ColumnProfiles.
• Heading-aware chunk metadata when ReaderHtmlOptions.ChunkByHeadings is enabled.
• HTML-to-Markdown profile, transform, converter, and visual round-trip option pass-through.
• A schema-v5 rich result containing semantic headings, quotes, code, footnotes, list markers, figures, tables, links, form controls, media visuals, metadata, and bounded data-URI image assets.
• MHTML root HTML, decoded related resources, archive diagnostics, and stable officeimo.html.mhtml capability evidence.
• ARIA heading levels and accessible link/image names in rich blocks, links, assets, visuals, JSON, and officeimo.html.* capability identifiers.

Boundaries

• Reader adapter configuration belongs here.
• HTML to Markdown conversion belongs in OfficeIMO.Markdown.Html.
• Shared extraction contracts belong in OfficeIMO.Reader.Core.

Targets and license

• Targets: netstandard2.0, net8.0, net10.0.
• License: MIT.

Dependency footprint

• External: AngleSharp/AngleSharp.Css only through OfficeIMO.Html.
• OfficeIMO: OfficeIMO.Reader.Core, OfficeIMO.Html, OfficeIMO.Email, OfficeIMO.Markdown, and OfficeIMO.Markdown.Html own MIME mechanics, parsing, projection, chunks, and rich results.

See the complete OfficeIMO package map for related formats and conversion paths.