Copy contents of an Open XML package part to a document part in a different package

This topic shows how to use the classes in the Open XML SDK for Office to copy the contents of an Open XML Wordprocessing document part to a document part in a different word-processing document programmatically.


Packages and Document Parts

An Open XML document is stored as a package, whose format is defined by ISO/IEC 29500-2. The package can have multiple parts with relationships between them. The relationship between parts controls the category of the document. A document can be defined as a word-processing document if its package-relationship item contains a relationship to a main document part. If its package-relationship item contains a relationship to a presentation part it can be defined as a presentation document. If its package-relationship item contains a relationship to a workbook part, it is defined as a spreadsheet document. In this how-to topic, you will use a word-processing document package.


Getting a WordprocessingDocument Object

To open an existing document, instantiate the WordprocessingDocument class as shown in the following two using statements. In the same statement, you open the word processing file with the specified file name by using the Open method, with the Boolean parameter. For the source file that set the parameter to false to open it for read-only access. For the target file, set the parameter to true in order to enable editing the document.

    using (WordprocessingDocument wordDoc1 = WordprocessingDocument.Open(fromDocument1, false))
    using (WordprocessingDocument wordDoc2 = WordprocessingDocument.Open(toDocument2, true))
    {
        // Insert other code here.
    }

The using statement provides a recommended alternative to the typical .Create, .Save, .Close sequence. It ensures that the Dispose method (internal method used by the Open XML SDK to clean up resources) is automatically called when the closing brace is reached. The block that follows the using statement establishes a scope for the object that is created or named in the using statement. Because the WordprocessingDocument class in the Open XML SDK automatically saves and closes the object as part of its System.IDisposable implementation, and because Dispose is automatically called when you exit the block, you do not have to explicitly call Save and Close─as long as you use using.


Structure of a WordProcessingML Document

The basic document structure of a WordProcessingML document consists of the document and body elements, followed by one or more block level elements such as p, which represents a paragraph. A paragraph contains one or more r elements. The r stands for run, which is a region of text with a common set of properties, such as formatting. A run contains one or more t elements. The t element contains a range of text. The following code example shows the WordprocessingML markup for a document that contains the text "Example text."

    <w:document xmlns:w="https://schemas.openxmlformats.org/wordprocessingml/2006/main">
      <w:body>
        <w:p>
          <w:r>
            <w:t>Example text.</w:t>
          </w:r>
        </w:p>
      </w:body>
    </w:document>

Using the Open XML SDK, you can create document structure and content using strongly-typed classes that correspond to WordprocessingML elements. You will find these classes in the DocumentFormat.OpenXml.Wordprocessing namespace. The following table lists the class names of the classes that correspond to the document, body, p, r, and t elements.

WordprocessingML Element Open XML SDK Class Description
document Document The root element for the main document part.
body Body The container for the block level structures such as paragraphs, tables, annotations and others specified in the ISO/IEC 29500 specification.
p Paragraph A paragraph.
r Run A run.
t Text A range of text.

For more information about the overall structure of the parts and elements of a WordprocessingML document, see Structure of a WordprocessingML document.


The Theme Part

The theme part contains information about the color, font, and format of a document. It is defined in the ISO/IEC 29500 specification as follows.

An instance of this part type contains information about a document's theme, which is a combination of color scheme, font scheme, and format scheme (the latter also being referred to as effects). For a WordprocessingML document, the choice of theme affects the color and style of headings, among other things. For a SpreadsheetML document, the choice of theme affects the color and style of cell contents and charts, among other things. For a PresentationML document, the choice of theme affects the formatting of slides, handouts, and notes via the associated master, among other things.

A WordprocessingML or SpreadsheetML package shall contain zero or one Theme part, which shall be the target of an implicit relationship in a Main Document (§11.3.10) or Workbook (§12.3.23) part. A PresentationML package shall contain zero or one Theme part per Handout Master (§13.3.3), Notes Master (§13.3.4), Slide Master (§13.3.10) or Presentation (§13.3.6) part via an implicit relationship.

Example: The following WordprocessingML Main Document part-relationship item contains a relationship to the Theme part, which is stored in the ZIP item theme/theme1.xml:

    <Relationships xmlns="…">
       <Relationship Id="rId4"
          Type="https://…/theme" Target="theme/theme1.xml"/>
    </Relationships>

© ISO/IEC29500: 2008.


How the Sample Code Works

To copy the contents of a document part in an Open XML package to a document part in a different package, the full path of the each word processing document is passed in as a parameter to the CopyThemeContent method. The code then opens both documents as WordprocessingDocument objects, and creates variables that reference the ThemePart parts in each of the packages.

    public static void CopyThemeContent(string fromDocument1, string toDocument2)
    {
       using (WordprocessingDocument wordDoc1 = WordprocessingDocument.Open(fromDocument1, false))
       using (WordprocessingDocument wordDoc2 = WordprocessingDocument.Open(toDocument2, true))
       {
          ThemePart themePart1 = wordDoc1.MainDocumentPart.ThemePart;
          ThemePart themePart2 = wordDoc2.MainDocumentPart.ThemePart;

The code then reads the contents of the source ThemePart part by using a StreamReader object and writes to the target ThemePart part by using a StreamWriter object.

    using (StreamReader streamReader = new StreamReader(themePart1.GetStream()))
    using (StreamWriter streamWriter = new StreamWriter(themePart2.GetStream(FileMode.Create))) 
    {
        streamWriter.Write( streamReader.ReadToEnd());
    }

Sample Code

The following code copies the contents of one document part in an Open XML package to a document part in a different package. To call the CopyThemeContent method, you can use the following example, which copies the theme part from "MyPkg4.docx" to "MyPkg3.docx."

    string fromDocument1 = @"C:\Users\Public\Documents\MyPkg4.docx";
    string toDocument2 = @"C:\Users\Public\Documents\MyPkg3.docx";
    CopyThemeContent(fromDocument1, toDocument2);

Important

Before you run the program, make sure that the source document (MyPkg4.docx) has the theme part set; otherwise, an exception would be thrown. To add a theme to a document, open it in Microsoft Word 2013, click the Page Layout tab, click Themes, and select one of the available themes.

After running the program, you can inspect the file "MyPkg3.docx" to see the copied theme from the file "MyPkg4.docx."

Following is the complete sample code in both C# and Visual Basic.


using DocumentFormat.OpenXml.Packaging;
using System.IO;

CopyThemeContent(args[0], args[1]);

// To copy contents of one package part.
static void CopyThemeContent(string fromDocument1, string toDocument2)
{
    using (WordprocessingDocument wordDoc1 = WordprocessingDocument.Open(fromDocument1, false))
    using (WordprocessingDocument wordDoc2 = WordprocessingDocument.Open(toDocument2, true))
    {
        ThemePart? themePart1 = wordDoc1?.MainDocumentPart?.ThemePart;
        ThemePart? themePart2 = wordDoc2?.MainDocumentPart?.ThemePart;

        // If the theme parts are null, then there is nothing to copy.
        if (themePart1 is null || themePart2 is null)
        {
            return;
        }

        using (StreamReader streamReader = new StreamReader(themePart1.GetStream()))
        using (StreamWriter streamWriter = new StreamWriter(themePart2.GetStream(FileMode.Create)))
        {
            streamWriter.Write(streamReader.ReadToEnd());
        }
    }
}

See also