OfficeIMO 3.6.1

OfficeIMO

OfficeIMO is the one-reference package for documents in .NET: Word, Excel, PowerPoint, PDF and Markdown, the conversions between them, OfficeConverter for files and folders, and the document reader for search and AI ingestion. It runs without Microsoft Office.

dotnet add package OfficeIMO

Targets netstandard2.0, net8.0 and net10.0, plus net472 on Windows, so .NET Framework applications get the same conversion routes. To keep a dependency small, reference the individual format packages instead.

Render page images

Use a loaded document's ToImage for one surface or ToImages for a batch. Both return OfficeImageExportResult with encoded Bytes, dimensions and diagnostics. SaveAsImage and SaveAsImages persist output and return conversion reports. The owning format's options inherit shared density, fonts, selection, limits and cancellation policies. Image rendering lists adapter packages and examples.

The package capability catalog describes available library routes; OfficeConverter.Routes lists the routes executable by OfficeConverter and registered adapters. Its single-file Convert operation does not turn an image route into a page directory or ZIP. Use the owning SaveAsImages API for page files.

Create documents and save them as PDF

using OfficeIMO;
using OfficeIMO.Excel;
using OfficeIMO.Excel.Pdf;
using OfficeIMO.Word;
using OfficeIMO.Word.Pdf;

Sale[] sales = [new("North", 182_400m), new("South", 141_900m), new("West", 97_300m)];

using (var report = WordDocument.Create("Sales.docx")) {
    report.AddHeading("Quarterly sales", level: 1);
    report.AddTable(sales);
    report.AddChart(OfficeChartType.Column, sales, nameof(Sale.Region), nameof(Sale.Revenue));
    report.Save();
    report.SaveAsPdf("Sales.pdf");
}

using (var book = ExcelDocument.Create("Sales.xlsx", new ExcelCreateOptions { Theme = OfficeTheme.Modern })) {
    book.AddSheet("Sales").AddTable(sales);
    book.Save();
    book.SaveAsPdf("Sales-workbook.pdf");
}

record Sale(string Region, decimal Revenue);

Convert files

OfficeConverter.Convert picks the route from the file extensions and returns an OfficeConversionReport:

using OfficeIMO;

OfficeConversionReport report = OfficeConverter.Convert("Sales.docx", "Sales.md",
    new OfficeConversionOptions { FileConflictPolicy = OfficePublicationPolicy.Replace, FailOnLoss = false });
foreach (OfficeDiagnostic diagnostic in report.Diagnostics) {
    Console.WriteLine($"{diagnostic.Severity} {diagnostic.Code}: {diagnostic.Message}");
}

By default an existing output is not replaced; FileConflictPolicy changes that. FailOnLoss = true stops a conversion before it writes anything the target cannot carry. OfficeConversionOptions.WordSave, ExcelSave and PowerPointSave set native save options, such as passwords, on the output.

Conversion preserves the source appearance by default. To give a plain document a selected appearance, pass an explicit theme:

OfficeConverter.Convert("Notes.md", "Notes.pdf", new OfficeConversionOptions {
    Theme = OfficeTheme.Boardroom
});

The common Theme option supports Word to PDF, HTML and native Word formats; Word 2003 XML and Flat OPC XML to Word; Markdown to Word, PDF and HTML; HTML to Word and PDF; and the registered Word/RTF, RTF/Word, RTF/PDF and RTF/HTML routes. Explicit adapter themes and authored HTML CSS take precedence. A route that cannot carry the theme rejects the request before writing output. In-memory folder batches accept themes; saved batch settings and resumable checkpoints reject them because their portable format does not store a theme.

Convert a folder

using OfficeIMO;

OfficeBatchReport batch = await OfficeConverter.ConvertAsync(
    Directory.EnumerateFiles("Reports", "*.docx"),
    outputDirectory: "Pdf",
    target: OfficeDocumentFormat.Pdf,
    new OfficeBatchOptions { MaxParallelism = 4, ResumeFrom = "Pdf/.officeimo-batch.json" });

Console.WriteLine($"{batch.Summary.Completed} converted, {batch.Summary.Reused} already done, {batch.Summary.Failed} failed");
foreach (OfficeBatchItemReport item in batch.Items) {
    Console.WriteLine($"{item.Status} {item.InputPath} -> {item.OutputPath}");
}

With ResumeFrom, a rerun reuses verified outputs from the checkpoint and converts only what is missing; RetryFailed retries recorded failures. The checkpoint format and saved options are the same on every framework.

Convert in memory

To{Format}() returns the target document model; the async form returns the model and its report together:

using OfficeIMO;
using OfficeIMO.Markdown;
using OfficeIMO.Word;
using OfficeIMO.Word.Markdown;

using MarkdownDocument source = MarkdownDocument.Parse("# Quarterly review\n\n- Revenue up 12%\n- Two open risks");
OfficeConversionResult<WordDocument> converted = await source.ToWordAsync();
using WordDocument word = converted.Value;
converted.Report.ThrowIfLoss();
word.Save("Review.docx");

Inspect any document

using OfficeIMO;

OfficeDocumentInfo info = OfficeDocument.Inspect("Review.docx", new OfficeInspectOptions { IncludeContent = false });
Console.WriteLine(info.Source);

OfficeIMO.Workflows and OfficeIMO.Workflows.IWork add further routes, such as Apple iWork files, through RegisterConversions().

See the repository README for the package map and the migration guide when upgrading.

Generated capability summary

This table is generated from the package-neutral OfficeIMO operation catalog. The detailed source contracts remain authoritative for feature-level behavior and limitations.

The complete rows for OfficeIMO are published in the generated operation contract.