The Top C# .NET Word API Libraries

Companies in every industry use Microsoft Word to create and manipulate nearly every kind of document. The ability to create accurate and well-formatted documents as quickly as possible has become a standard part of how businesses operate.

In many cases, this requires that they use document processing solutions that can be scaled as needed and that can efficiently handle the multitude of actions required to produce the documents.

In the .NET environment, C# .NET Word API libraries are used to integrate these valuable capabilities into almost any project that requires Word document processing.

This article will explore some of the most popular C# .NET Word API libraries, review the elements that make Microsoft Word such a powerful word-processing tool, and compare the leading options. We will examine the following features and functionalities:

• Programmatically create, load, modify, save, or inspect MS Word documents
• Read-write support for DOCX, DOTM, DOCM, and DOTX file formats
• Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats
• Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts
• Report (Data) Templates to create data-bound documents
• Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes
• Shape and geometry type presets and themed shape styles
• Image insertion with various formatting options
• Find and replace functionality
• OfficeMath support

Document Solutions for Word by MESCIUS

Programmatically create, load, modify, save, or inspect MS Word documents

You can generate, load, edit, and save Word documents. Capabilities include loading existing DOCX files and editing the files by changing elements such as text, formatting, and theme colors. You can also copy paragraphs, merge documents, and execute many other types of modifications.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

There is full support for DOCX, DOTM, DOCM, and DOTX files. You're also able to export documents to PDF and PDF/A formats as well as enable password protection for those formats.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

You can read files with flat Open XML formats, easily accessing application data.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

You can use Tate Chu Yoko and East Asian vertical text in DOCX files while maintaining the formatting when exporting those documents to PDF or image formats. The image formats include TIFF, JPG, PNG, and SVG.

Report (Data) Templates to create data-bound documents

Populate report templates for documents, like invoices, legal agreements, and contracts, by binding them to data sources. The templates can be converted to PDF or multiple image formats and include advanced layout features like tables, repeating multi-table rows, and much more.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

Customize your documents with built-in and user-defined styles for document elements, including themes, text, paragraphs, tables, and lists. You can also choose font fill and line styles as well as create linked styles for paragraphs and character runs.

Shape and geometry type preset, themed shape styles

Use a wide range of geometric shapes, shape presets, and theme-based shape styles to enrich your Word documents. There are 188 geometry types, 42 themed shaped styles, and 29 shape presets.

Image insertion with various formatting options

You can add images to documents and edit the images by adjusting color, transparency, contrast, and brightness.  The images can be imported from data files and streams.

Find and replace functionality

This functionality includes multiple options, such as locating and replacing all occurrences of a specific text, finding and replacing text and its content, and replacing placeholders with data in a template. You can also insert the body of a document at a found text in another document.

OfficeMath support

Display, add, read, and edit Office Math content in Word documents. There is also support for converting Office Math to MathML and the reverse.

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Document Solutions for Word (DsWord) provides a comprehensive set of features and functionalities that facilitate document processing just as well as MS Word. The C# .NET Word API library emulates the perfect MS Word stand-in. It can handle tasks like exporting Word documents to PDF format while preserving text formatting. You can set custom document properties, adjusting the style options for characters, paragraphs, tables, and lists to maintain control of the appearance and function of your document.

The API also allows you to add content from the vast selection of geometric shapes. Documents can be customized even further with the addition of images, formatted as needed. The process for populating report templates is made efficient with the data binding feature. You can also use OfficeMath just as you would in MS Word.

Even with its vast range of features and functionalities, DsWord is very simple to use. It can efficiently handle all the Word document processing tasks your .NET project requires.

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Aspose.Words for .NET

Programmatically create, load, modify, save, or inspect MS Word documents

Aspose.Words for .NET allows you to generate, modify, convert, render, and print documents. There is no need for Office Automation tools or third-party applications.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

Read-write support includes DOC, DOCX, DOTM, and DOTX. There is also read-only support for DocPreWord60 for documents in the Word 6 or Word 95 format.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

Users can load and save FlatOPC, FlatOPCMacroEnabled, FlatOPCTemplate, and FlatOPCTemplateEnabled formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

Aspose.Word’s layout engines work similarly to MS Word’s page layout engine. Users can print to PDF, JPEG, and PNG image formats with RTL, vertical, and East Asian texts displayed properly. However, you must use and install TrueType fonts on the machine where you are converting the documents.

Report (Data) Templates to create data-bound documents

There are predefined templates for reports, contracts, invoices, and other forms that can be linked to data sources, such as databases or business objects.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

Users can customize their documents by using a collection of built-in and user-defined styles for characters, paragraphs, and tables. They can also define their own versions of these items.

Shape and geometry type presets and themed shape styles

Aspose.Words provides shape types and styles. Its shapes class includes numerous geometric shapes as well as an AutoShape, textbox, freeform, OLE object, ActiveX control, and picture.

Image insertion with various formatting options

End users can insert images in JPG, PNG, GIF, TIFF, EMF, SVG, and more. Formatting options include alignment and cropping, among others.

Find and replace functionality

The search and replace function can speed up formatting tasks.

OfficeMath support

You can manage Office Math objects, determining how it is displayed (justified, inline, separate line, etc.).

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Aspose provides developers with plenty of features. It has expansive Word file compatibility so that you can migrate between MS Office versions with no hassle. It enables many actions required to handle the files, including conversion and printing. The ability to output to other formats while maintaining the original formatting of the Word document is an advantage of the library.

Numerous templates are available for report creation, and the data-binding capability adds efficiency. Aspose enables simple document customization with a large style selection of options for numerous elements, including images, characters, layouts, and lists. It is a versatile API library suitable for .NET projects with intensive document processing tasks.

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Syncfusion Essential DocIO

Programmatically create, load, modify, save, or inspect MS Word documents

End users can create, convert, read, and write MS Word documents.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

Essential DocIO library provides read-write support for DOC, DOT, DOCX, DOTX, DOCM, DOTM, WordML, and RTF file formats. There is also conversion capability to HTML, Markdown, PDF, and image.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

Syncfusion Essential DocIO does not offer read-only support for these formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

You can export Word documents as a high-quality image, PDF file, and EPUB with support for RTL, vertical, and East Asian texts.

Report (Data) Templates to create data-bound documents

You can create templates and use built-in elements, like form-filling and mail merge, to populate the forms. You can also design reports using Microsoft Word and use DocIO to dynamically populate them with data.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

DocIO provides predefined styles for characters, paragraphs, lists, and tables. Users can also create customized styles.

Shape and geometry type presets and themed shape styles

You can use preset and user-defined shapes and geometry in DOCX and WordML format documents. You can also apply the same formatting properties for children of group shapes.

Image insertion with various formatting options

DocIO provides support for both inline and absolute positioned images in multiple formats such as JPG and PNG. It also provides formatting options like rotation.

Find and replace functionality

Locate and change specific text throughout an entire document. You can search for a particular text you’d like to change and replace it with another text or part of the document.

OfficeMath support

The .NET Word Library doesn’t provide Office Math support. Instead, it provides WMath DOM and LaTeX to create and edit equations or formulas in Word.

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Syncfusion Essential DocIO’s object model is flexible and simple to use. It supports multiple document formats and provides the capabilities for efficiently handling those documents. You can create Word documents from scratch and convert them to other formats, including PDF and HTML.

Essential DocIO enables developers to perform many essential document-processing tasks. You can generate and fill in report templates with features like mail merge and form-filling. However, you will run into issues with reading XML files as the library does not appear to support FlatOPC or other XML formats.

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Telerik Document Processing – WordsProcessing Library

Programmatically create, load, modify, save, or inspect MS Word documents

The library lets users create, edit, export, and convert various MS Word document formats.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

There is read-write support for DOC and DOCX formats. There is currently no support for DOTM, DOCM, and DOTX files.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

Telerik WordsProcessing Library does not offer read-only support for these formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

You can export to PDF, but there is no support for RTL. Support for vertical or East Asian texts is unclear.

Report (Data) Templates to create data-bound documents

Telerik WordsProcessing Library does not appear to offer report template functionality.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

The library supports predefined style definitions for characters, paragraphs, and tables. You can specify elements like fonts, colors, and graphic effects with document themes. There is also support for list templates.

Shape and geometry type presets and themed shape styles

There are shape and geometry-type presets. However, when exporting to formats other than DOCX, the shapes will be lost.

Image insertion with various formatting options

There is support for 12 image formats, including JPEG, ICON, and SVG. You can adjust image attributes such as size, rotation, and source.

Find and replace functionality

The library enables you to search for a string and replace all matches. You can also replace only the styling of the matches.

OfficeMath support

There is no support for inserting equations and formulas, including Office Math.

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Telerik’s Word Processing Library is not as fleshed out as other .NET Word libraries. For example, the MS Word native file format compatibility is limited to DOC and DOCX. There is no support for flat files or any capability to insert formulas and equations using Office Math or other math typography components.

However, it does provide a full range of actions to handle select MS Word formats. Devs will find the functionality to format and customize documents with an array of built-in and user-defined style definitions for various document elements. There is a selection of images available for insertion in Word files, plus options to customize them with multiple formatting choices. DOCX files can be further enriched with shapes and geometric types, as needed, but those features will be lost if you need to export to another format.

While Telerik’s WordProcessing Library lacks some key functionalities, it can still meet the needs of document processing centered on the DOCX format.

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Spire.Doc for .NET

Programmatically create, load, modify, save, or inspect MS Word documents

You can create, convert, read, write, compare, and print MS Word documents.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

Spire.Doc supports Word 97-2003 /2007/2010/2013/2016/2019 files.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

Spire.Doc does not offer read-only support for these formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

The library supports RTL in Word documents but not when they are converted to PDF or image formats.

Report (Data) Templates to create data-bound documents

You can create report templates programmatically and use mail merge to fill in the data. There does not appear to be any built-in templates available.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

You can use document themes as well as predefined character, paragraph, table, and list styles to customize documents.

Shape and geometry type presets and themed shape styles

Users can insert predefined shapes and geometry types. You can also create shape groups that share the same shape styles.

Image insertion with various formatting options

You can customize Word documents with images, including JPG, PNG, and SVG formats, as well as set attributes like transparency, size, wrapping styles, and position.

Find and replace functionality

The library provides find and replace functions to speed up the editing process.

OfficeMath support

There is no Office Math capability, but the library does support LaTex Math Symbols and MathML Code.

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With its capabilities, Spire.Doc for .NET is a suitable option for Word document processing projects. The API is useful to process many of the native MS Word file formats through 2019. There is support for advanced formatting with styles and images. While there is no OfficeMath support, Spire.Doc supports LaTex Math and MathML Code, which are viable alternatives.

Though support for data binding with templates is missing, the API does enable mail merge to help populate the document. Editing can be streamlined with the find and replace function. There is functionality to export to PDF and image formats, but as with some other APIs, the output cannot maintain advanced features like RTL, vertical, or East Asian texts.

Despite its limitations, Spire.Doc for .NET still offers a solid platform for managing less complex Word documents.

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GemBox.Document

Programmatically create, load, modify, save, or inspect MS Word documents

The component enables users to read, write, convert, and print MS Word files.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

For native MS Word formats, read-write support is limited to DOC and DOCX. There is also support for ODT, PDF, PDF/A, XPS, HTML, RTF, XML, and TXT formats.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

GemBox.Document does not offer read-only support for these formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

Documents can be exported to PDF and image formats with support for RTL texts.

Report (Data) Templates to create data-bound documents

There are no built-in report templates, but you can upload template files that have predefined layouts, formatting, and styles and use mail merge to populate them.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

You can use themes as well as predefined style definitions for paragraphs, characters, lists, and tables or create and edit your own.

Shape and geometry type preset, themed shape styles

There are preset shape types and geometric objects, line curves, triangles, rectangles, etc. The shapes and geometric objects organized into groups adhere to the group’s layout and styling.

Image insertion with various formatting options

Image compatibility covers PNG, JPEG, GIF, TIFF, SVG, EMF, and WMF with formatting capability for position and size.

Find and replace functionality

GemBox provides the find and replace function to replace specified strings with updated strings. There is also functionality to replace strings with hyperlinks, pictures, tables, and other content.

OfficeMath support

There is no OfficeMath support, but the library provides a preservation feature that allows you to preserve unsupported features (in this case, equations) from input to output in the same format.

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GemBox.Document is a straightforward component that enables improved file processing capability for any project. It is not as expansive as other .NET Word API libraries, but you will find the tools you need for basic document processing. There are built-in templates that can be customized and populated using mail merge. The find and replace functionality allows you to not only replace text with other text but also with other content like images and hyperlinks. While there is no OfficeMath support, you can maintain math symbols in existing Word documents.

The main highlight of the library is its simplicity and uncomplicated design. There are some limitations, such as the lack of a math typography feature, but this library is still suitable for basic Word documents.

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Plumsail Documents

Programmatically create, load, modify, save, or inspect MS Word documents

Create, save, and convert select MS Word documents.

Read-write support for DOCX, DOTM, DOCM, and DOTX file formats

There is read-write support for DOC and DOCX file formats. Support for CSV files is read-only.

Read-only support for FlatOPC, FlatOpcMacroEnabled, FlatOpcTemplate, and FlatOpcTemplateEnabled formats

Plumsail Documents does not offer read-only support for these formats.

Export documents to PDF or image formats, with support for RTL, vertical, and East Asian texts

You can convert Word (DOC and DOCX) to PDF with some support for maintaining text formatting.

Report (Data) Templates to create data-bound documents

There are numerous preformatted, editable report templates that can be automatically populated from data collected from a web form, CRM, ERP, or other apps.

Support for built-in and user-defined character, paragraph, and table styles, list templates, and themes

There is limited built-in style support for lists.

Shape and geometry type preset, themed shape styles

Plumsail Documents does not appear to offer support for shape and geometry type presets or styles.

Image insertion with various formatting options

You can add images to DOCX templates with formatting options that include flipping, stretching, resizing, and rotation.

Find and replace functionality

Strings in templates can be changed with the “replace” value formatter.

OfficeMath support

There is no support available for OfficeMath with Plumsail Documents.

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You can execute standard actions for Word documents, such as create, save, merge, and convert, but customization seems limited. There does not appear to be support for adding shapes and personalizing characters, paragraphs, or tables. There is no OfficeMath support or support for an equivalent. You can replace strings in documents and convert documents to PDF formats. There is also some support for lists.

The primary focus of Plumsail Documents seems to be templates. The template creation process is simple and fast with many built-in templates available if required. The templates can be bound to data sources like web forms. Simple customizations for these templates, like images, are also offered.

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Conclusion

When choosing the top C# .NET Word API library, the Word document management needs of your project should always be the priority. While it’s true that all of these libraries are popular choices among developers, Document Solutions for Word by MESCIUS stands out as the ideal solution for working with Word documents programmatically in a .NET environment with its wide range of essential Word-like features and functionalities.

You can use Document Solutions for Word to work with all the popular Word file formats, including macro-enabled and template files. The API’s file compatibility also extends to reading flat OPC files.

Customization of Word documents is a notable benefit. There are numerous built-in style options for document elements, like text, paragraphs, and lists, to create almost any type of document. Documents can be enriched with images, tables, numerous geometric shapes, mathematical equations, and more. Personalization is a key benefit, as you can create customized styles for many of these elements. Document Solutions for Word provides these features and numerous options for them. You’re also able to use the find and replace feature in more ways than you would with other .NET Word API libraries to streamline the editing process.

Another highlight is that Document Solutions for Word integrates seamlessly with PDF files so that users can take advantage of this universal format. You can export to PDF and image formats with the assurance of maintaining the original format, even for documents that include languages with top-to-bottom and right-to-left layouts.

The API also facilitates how well you can create and customize templates. It streamlines the data population process with its data-binding feature, and as with the other supported Word formats, you can export the files to PDF and image files while maintaining formatting.

While Aspose.Words for .NET is a formidable alternative, Document Solutions for Word by MESCIUS is a feature-rich, easy-to-learn C# .NET API library, ideal for any .NET project requiring Word document management capabilities. Whether you need to perform basic operations or are seeking advanced features, Document Solutions for Word meets the needs of nearly any project for document processing.