.NET Word Library | C# and VB.NET Word APIs & Conversions

.NET Word Library overview

The .NET Word Library is a feature-rich and high-performance library that allows you to add advanced Word document processing functionalities to any .NET application. It allows you to create, read, and edit Word documents programmatically without Microsoft Office or interop dependencies. It allows you to create complex reports by merging data from various data sources using its powerful mail merge engine. This library also provides functionalities for merging, splitting, organizing Word documents, and finding and replacing text with ease.

Overview Diagram of .NET Word Library.

General information

Blazing-fast performance

Optimized for a server environment where speed and low memory usage are critical, DocIO works much faster and consumes less memory when compared to Office automation libraries.

No server deployment fees

There are no distribution fees, per-server licensing fees, or royalties, making DocIO very cost-effective.

Powerful and comprehensive APIs

All the elements of a typical Word document like text, formatting, images, tables, sections, headers, and footers are accessible through a comprehensive set of APIs. It only takes a few lines of code to create or manipulate richly formatted Word documents.

Supported file formats

Create, read, and edit popular text file formats like DOC, DOT, DOCM, DOTM, DOCX, DOTX, HTML, RTF, TXT, and XML (WordML). Convert Word documents to PDF, image (PNG, BMP, JPEG, EMF, TIFF), ODT, and EPUB files.

Start reports with Word and finish with DocIO

Design reports using Microsoft Word and uses DocIO to dynamically populate them with data. The final report then can be saved to a Word file or exported to other supported formats like PDF.

Mail merge

Simple mail merge using .NET Word Library.

Simple mail merge

Performs mail merge by repeating the entire document automatically for every record in the data source. Multiple documents can also be created from a Word template.

Group mail merge using .NET Word Library.

Group mail merge

Performs mail merge by repeating a particular region of the document automatically for every record in the data source.

Nested mail merge using .NET Word Library.

Nested mail merge

Generates complex reports by repeating nested region of document with relational data.

Data sources for performing mail merge.

Data sources

Populate the template Word document with data from common data sources like arrays, ADO.NET objects, IEnumerable collection, dynamic objects, and XML.

Format the merged data during mail merge.

Formatting

Format the merged text, numeric values, and date-times automatically with the help of field switches.

Merge image during mail merge.

Images

When the prefix “image:” is added to the merge field name, it places the image in the place of the merge field.

Mail merge events to customize the merged data.

Mail merge events

Customize a document during mail merge by formatting and editing the merged text, numeric and image data with mail merge events, and also the layout of the document by inserting breaks.

Options to customize mail merge functionality.

Options

The library supports intuitive options like mapping merge fields with fields in a data source; retrieving merge field names; and removing merge fields that are not merged, empty paragraphs, and empty groups.

For more information, check out our mail merge features.

Document elements

Sections in Word documents.

Section

Organize document contents with sections for grouping contents and making the contents start on a new page, odd page, even page, or continue on the same page.

Header and footer in Word documents.

Header and footer

Add information like title, author, branding, or page number to the header or footer repeat it at the top or bottom of every page. Use any header and footer type, such as different first page and different odd and even pages.

Text in Word documents.

Text

Create or edit documents in any supported language. Use left-to-right and right-to-left text, also.

Images in Word documents.

Images

Insert images in a document with all the common layout options like text wrapping, position, and size. Use all common image formats: PNG, BMP, JPEG, TIFF, GIF, EMF, WMF, SVG, etc.

Bookmarks in Word documents.

Bookmarks

Create and insert bookmarks to identify a part of the document for future reference.

Hyperlinks in Word documents.

Hyperlinks

Create a link in a document for quick access to webpages, files, email, bookmarks, etc.

Fields in Word documents.

Fields

Add dynamic information like title, time, and page number in a Word document that updates automatically. Update commonly used fields like merge field, IF field, date-time, page number, document properties, etc.

Text box in Word documents.

Text box

Showcase important text or quotes in a document within a text box. Insert and edit text, and format and remove a text box.

Shapes in Word documents.

Shape

Add all the predefined shapes in Word Open XML format documents (DOCX, DOTX, DOCM, DOTM, Word XML). Insert and edit text, and format and remove an existing shape.

Charts in Word documents.

Charts

Graphically represent a set of data with common chart types like column, line, pie, and bar in Word Open XML format documents (DOCX, DOTX, DOCM, DOTM, Word XML). Add and modify data, title, axes, data labels, legends, trendlines, etc., and format and remove an existing chart.

OLE objects in Word documents.

OLE objects

Embed any common file format within a Word document. Extract the embedded OLE object data from a Word document and save its native file format.

Footnote and endnote in Word documents.

Footnote and endnote

Additional information like detailed descriptions, references, or credits can be added at the end of each page and document. Edit and remove a note from a document.

Properties of a Word documents.

Document properties

Read and write document information with built-in document properties. Use custom document properties and document variables.

Accessible Word documents.

Accessible document

Create accessible Word documents with 508 standard compliance with directly accessible elements like text and tables and set alternate text for all graphical elements like images, text boxes, shapes, and charts.

Formatting

Text formatting in Word documents.

Text formatting

Customize the appearance of the text with several text-level formatting options: font family, size, style, underline, strikethrough, text color, highlight, subscript, superscript, etc.

Paragraph formatting in Word documents.

Paragraph formatting

Customize the appearance of a paragraph with several paragraph-level formatting options: indents, alignment, spacing, tab stops, text direction, etc.

Bullets and numbering in Word documents.

Bullets and numbering

Organize items or create an outline of the document with bullets and numbering ranging from single-level to multilevel lists.

Page settings in Word documents.

Page settings

Design the structure and layout of document pages with several properties like size, margins, orientation, columns, line numbers, borders, page background, watermarks, etc.

Styles in Word documents.

Styles

Create and apply styles to ensure consistency within a document. Use predefined and custom character styles, paragraph styles, and predefined table styles.

Tables

Create, insert, and delete tables in a document. Use nested tables, also.

Edit tables in Word documents.

Edit

Edit an existing table in a document like by merging cells, adding or removing cells and rows, and resizing cells.

Format tables in Word documents.

Format

Format a table with several properties: indent, alignment, cell margins and spacing, borders, shadings, repeat header row, break row across pages, etc.

Table styles in Word documents.

Styles

Give a polished look to tables by applying built-in styles and conditional styling options like first row, last row, banded rows, first column, last column, and banded columns.

Edit and organize

Copy and paste contents in Word documents.

Copy and paste

Copy part of a document and insert that part into the same or a different document with several formatting options like using destination styles and keeping source formatting. Use all the common paste options like in Microsoft Word.

Edit bookmark contents in Word documents.

Edit bookmark contents

Navigate to a bookmark in the document and insert, edit, retrieve, or delete its content. Also replace the bookmarked contents with text, a part of a document, or an entire document.

Merge multiple Word documents.

Merge

Merge multiple documents into a single document with several formatting options like using destination styles or keeping source formatting.

Learn more about merge Word documents

Split Word document into multiple small documents.

Split

Split a document into multiple small documents based on sections, placeholder text, or any document element.

Learn more about split Word documents

Find and replace

Find text in Word documents.

Find text

Find text by matching whole words, then highlight or format it. Also, find text patterns using regular expressions.

Replace text in Word documents.

Advanced replace

Replace the text or text pattern with another text, a part of a document, or an entire document. Retain source or target formatting.

Create, insert, and edit a table of contents (TOC) to outline the contents of a document. Update or rebuild the TOC after modifying a Word document. Build TOC based on heading and custom styles, including page numbers, and hyperlink for easy navigation.

Content controls

Design form using content controls in Word documents.

Design form

Create and insert content controls like plain text, rich text, pictures, checkboxes, combo boxes, dropdown lists, and date pickers in the Word Open XML format documents (DOCX, DOTX, DOCM, DOTM, Word XML). Group a part of a document with block content control.

Restrict editing the content of a content control.

Restrict editing

Protect the content of a content control from being edited by locking its content. Also prevent deleting a content control from the document.

Bind the content control with XML elements.

Binding

Bind content controls to an element in the custom XML part that is embedded in a document.

Security

Encrypt and decrypt Word documents.

Encrypt and decrypt Word documents

Encrypt a Word document with a password and open an encrypted Word document with a valid password.

Protect Word documents.

Protect Word documents

Restrict edit permissions for specific content in a Word document, and control what type of changes can be made to the document.

Form filling

Form filling with form fields in Word documents.

Form fields

Create fillable forms with legacy form fields in Word documents. Fill the form fields and extract filled data from the form fields effortlessly.

Form filling with content controls in Word documents.

Content controls

Create more functional forms with content controls like plain text, rich text, pictures, checkboxes, combo boxes, dropdown lists, and date pickers in Word Open XML format documents. Fill the form and extract filled data from the content controls effortlessly.

Review

Comments in Word documents.

Comments

Create and insert comments in a document to add notes about a part of the document while reviewing. Also, edit and remove an existing comment from a document.

Accept and reject changes in Word documents.

Accept and reject changes

Accept and reject changes that are tracked within a Word document.

Compare Word documents.

Compare

Compare two Word documents and highlight the changes, such as insertions, deletions, and formatting, as tracked changes.

Feature matrix

Document Content Features	WORD 97-2003	WORD 2007-2016	RTF
Create a Word document from scratch or edit an existing Word document.
Open an existing Word document from file system or stream.
Save the Word document to file system, stream, or stream it to the client browser.
Create, access, and modify paragraphs and text.
Create, access, and modify tables, rows, and cells.
Create, access, and modify hyperlinks.
Create, access, and modify bookmarks.
Rebuild and update a table of contents.
Create, access, and modify fields.
Update fields such as IF, formula, and other popular field types.
Update Page and NumPages fields.
Create, access, and modify footnotes and endnotes.
Create, access, and modify images.
Create, access, and modify shapes.
Group and ungroup shapes.
Insert text and picture watermarks.
Create, access, and modify OLE objects from the document.
Create, access, and modify charts .
Create, access, and modify mathematical equations.
Create equations using LaTeX.
Access and modify built-in document properties.
Create, access, and modify custom document properties.
Update paragraph, word, and character count.
Update page count.
Access, create, and modify document sections, headers, and footers.
Iterate over document content.
Access and move elements between documents.
Insert HTML text.

Form filling	WORD 97-2003	WORD 2007-2016	RTF
Create, access, and modify form fields (text, checkbox, dropdown).
Create, access, and modify structured document tags (rich text, plain, date picker, picture, dropdown list, and combo box content controls).
Bind content controls to custom XML parts (XML mapping).
Lock content controls.

Formatting	WORD 97-2003	WORD 2007-2016	RTF
Format characters including font size, color, name, bold, italic, underline, and more.
Format paragraphs including line spacing, alignment, indentation, spacing before and after, keep with next, and more.
Format bulleted and numbered lists including numbering and levels.
Format tables including alignment, borders, and shading.
Access and modify all section properties including paper size, margins, and orientation
Access, create, and modify character styles.
Access, create, and modify paragraph styles.
Apply built-in and custom table styles.

Review	WORD 97-2003	WORD 2007-2016	RTF
Create, access, and modify comments.
Accept and reject all track changes in a document.
Accept and reject changes of a particular reviewer.
Compare two Word documents

Merge and split	WORD 97-2003	WORD 2007-2016	RTF
Merge multiple Word documents into one.
Split large Word documents into smaller documents by sections, headings, bookmarks, and placeholders.

Mail merge	WORD 97-2003	WORD 2007-2016	RTF
Create, access, and modify merge fields.
Retrieve mail merge field names.
Insert images during mail merge.
Perform mail merge on documents that contain complex merge fields (conditional merge field).
Perform mail merge for a specified region.
Perform mail merge on reports that contain relational details (parent-child data).
Perform mail merge from any .NET data source such as string array, DataSet, DataTable, DataView, and DataReader.
Perform mail merge from any data source such as IEnumerable collection and dynamic objects.
Format the merged text, images, or other elements during mail merge.
Event hander to bind data for unmerged fields.
Map the merge field names with column names in the data source.
Skip to merge particular a image during the mail merge process.
Start a new page for each group of records.

Find and replace	WORD 97-2003	WORD 2007-2016	RTF
Find first occurrence of a specific text that matches the whole word and casing.
Find a specified pattern using a regular expression.
Find all occurrences of a specific text that matches the whole word and casing.
Replace a text with the same formatting.
Find and replace a text that extends to several paragraphs.
Find and replace a text with the document content (paragraph or table).
Find and replace a text with the content of another Word document.
Find elements (image, content control, chart, and more) in a document based on specified properties and their corresponding values.

Bookmarks	WORD 97-2003	WORD 2007-2016	RTF
Create and manipulate bookmarks.
Navigate to a specific bookmark.
Retrieve document content between the specified bookmarks and merge to an existing or a new document.
Insert text or part of a document content between the specified bookmarks.
Replace the content of a document between specified bookmarks with a text or part of another document.
Delete document content between specified bookmarks.

Security	WORD 97-2003	WORD 2007-2016	RTF
Open the password protected documents.
Protect the documents with passwords.
Restrict editing the documents.

File formats	Read	Write
Word 97-2003 formats (.doc, .dot)
Word 2007-2016 formats (.docx, .dotx, .docm, .dotm, *.xml)
Word 2003 XML Document (*.xml)
OpenDocument Text (*.odt)
RTF
HTML
Text
PDF
EPUB
Image (PNG, BMP, JPEG, EMF, TIFF)

PDF and image conversions	WORD 97-2003	WORD 2007-2016	RTF
Convert Word to PDF
Convert Word to PDF/A
Convert Word to PDF/UA (Section 508 compliant)
Create fillable PDF from Word document.
Convert Word to image (PNG, BMP, JPEG)
Convert a specific page in a Word document into an image (thumbnail image).
Convert a specified range of pages in a Word document into images.
Use alternate fonts from installed fonts during Word to PDF or image conversion.
Use alternate fonts without installing on the machine during Word to PDF or image conversion.