Extract text structure

GroupDocs.Parser provides the functionality to extract the text structure from documents by the GetStructure method:

XmlReader GetStructure();

This method returns XML representation of a document. A document has the following structure:

TagDescription
documentThe root tag
sectionRepresents a section of the document. Depending on the document type, it can represent a worksheet, a slide and so on. Can contain the following attributes:
  • style - the style of the section
  • name - the name of the section (for example, the name of the sheet)
pRepresents a text paragraph. Can contain the following attribute:
  • style - the style of paragraph
ulRepresents an unordered list
olRepresents an ordered list
liRepresents a list item
shapeRepresents a shape object.
tableRepresents a table
trRepresents a table row
tdRepresents a table cell. Can contain the following attributes:
  • rowIndex - the zero-based index of the row
  • columnIndex - the zero-based index of the column
  • rowSpan - the total number of rows that contain the table cell
  • columnSpan - the total number of columns that contain the table cell

Tags have the following relations:

  • document tag can contain any number of section tags
  • section tag can contain any number of p, ul, ol or table tags in any sequence
  • table tag can contain any number of tr tags
  • tr tag can contain any number of td tags
  • td tag can contain one p tag

The p and li tags can contain hyperlink, strong, em tags and the value that represents a text:

)

TagDescription
hyperlinkRepresents a hyperlink. Can contain the following attribute:
  • link - URL
strongRepresents a strong emphasis (bold text)
emRepresents a regular emphasis (italic text)
brRepresents a line break (empty tag)

Features of text extraction for different formats

Word processing documents

Word processing documents have a more complex table cell and paragraph can contain any number of shapes.

A table cell can contain any number of paragraphs, lists and tables:

A shape can contain a single hyperlink (empty tag) for the entire shape and any number of paragraphs, lists or tables:

Presentations

Presentations have a more complex table cell and section can contain any number of shapes.

A table cell can contain any number of paragraphs or lists:

A shape can contain a single hyperlink (empty tag) for the entire shape and any number of paragraphs or lists:

Spreadsheets

Spreadsheets have the following document structure:

It’s more simple than others. A section can contain any number of shapes and only one table. A shape can contain a single hyperlink (empty tag) for the entire shape and any numbers of paragraphs.

Examples

Here are the steps to extract hyperlinks from the document:

  • Instantiate Parser object for the initial document;
  • Call GetStructure method and obtain XmlReader object;
  • Check if reader isn’t null (text structure extraction is supported for the document);
  • Process the XML document.

The following example shows how to extract hyperlinks from the document:

// Create an instance of Parser class
using (Parser parser = new Parser(filePath))
{
    // Extract text structure to the XML reader
    using (XmlReader reader = parser.GetStructure())
    {
        // Check if text structure extraction is supported
        if (reader == null)
        {
            Console.WriteLine("Text structure extraction isn't supported.");
            return;
        }

		// Process the XML document
        // Read the XML document to search hyperlinks
        while (reader.Read())
        {
            // Check if this is a start element with "hyperlink" name
            if (reader.NodeType == XmlNodeType.Element && reader.IsStartElement() && reader.Name.ToLowerInvariant() == "hyperlink")
            {
                // Extract "link" attribute
                string value = reader.GetAttribute("link");
                if (value != null)
                {
                    Console.WriteLine(value);
                }
            }
        }
    }
}

The following document:

has the following text structure:

<?xml version="1.0"?>
<document>
  <section>
    <p style="HEADING1">
      <shape>
        <p style="HEADING1">
          Lorem ipsum dolor sit amet, <hyperlink link="google.com">consectetuer</hyperlink> adipiscing elit. Maecenas porttitor congue massa.
        </p>
      </shape>Lorem
    </p>
    <p>
      Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed <hyperlink link="bing.com">pulvinar ultricies</hyperlink>, purus lectus <strong>malesuada</strong> libero, sit amet commodo magna eros quis urna.
    </p>
    <ol>
      <li>Nunc viverra imperdiet enim. </li>
      <li>Fusce est.</li>
    </ol>
    <p>Vivamus a tellus. </p>
    <ul>
      <li>
        Pellentesque <em>
          <strong>habitant morbi tristique senectus et netus et</strong>
        </em> malesuada fames ac turpis egestas.
      </li>
      <li>Proin pharetra nonummy pede. </li>
      <li>Mauris et orci. </li>
      <li>Aenean nec lorem.</li>
    </ul>
    <table>
      <tr>
        <td rowIndex="0" columnIndex="0" rowSpan="1" columnSpan="1">
          <p>In porttitor.</p>
        </td>
        <td rowIndex="0" columnIndex="1" rowSpan="1" columnSpan="1">
          <p>
            Donec laoreet <strong>nonummy</strong> augue.
          </p>
        </td>
        <td rowIndex="0" columnIndex="2" rowSpan="1" columnSpan="1">
          <p>
            Suspendisse dui purus, <em>
              <strong>scelerisque</strong>
            </em> at, vulputate vitae, pretium mattis, nunc.
          </p>
        </td>
        <td rowIndex="0" columnIndex="3" rowSpan="1" columnSpan="1">
          <p>Mauris eget neque at sem venenatis eleifend. </p>
        </td>
      </tr>
      <tr>
        <td rowIndex="1" columnIndex="0" rowSpan="1" columnSpan="1">
          <p>Ut nonummy.</p>
        </td>
        <td rowIndex="1" columnIndex="1" rowSpan="1" columnSpan="1">
          <p>
            Fusce <hyperlink link="google.com">aliquet pede</hyperlink> non pede.
          </p>
        </td>
        <td rowIndex="1" columnIndex="2" rowSpan="1" columnSpan="1">
          <p>Suspendisse dapibus lorem pellentesque magna.</p>
        </td>
        <td rowIndex="1" columnIndex="3" rowSpan="1" columnSpan="1">
          <p>Integer nulla.</p>
        </td>
      </tr>
      <tr>
        <td rowIndex="2" columnIndex="0" rowSpan="3" columnSpan="1">
          <p>Donec blandit feugiat ligula.</p>
        </td>
        <td rowIndex="4" columnIndex="1" rowSpan="1" columnSpan="1">
          <p>
            Donec hendrerit, felis et <em>imperdiet</em> euismod, purus ipsum pretium metus, in lacinia nulla nisl eget sapien.
          </p>
        </td>
        <td rowIndex="2" columnIndex="2" rowSpan="3" columnSpan="1">
          <p>
            <strong>Donec</strong> ut est in lectus consequat consequat.
          </p>
        </td>
        <td rowIndex="2" columnIndex="3" rowSpan="3" columnSpan="1">
          <p>Etiam eget dui. Aliquam erat volutpat.</p>
        </td>
      </tr>
    </table>
    <p>Sed at lorem in nunc porta tristique. Proin nec augue.</p>
  </section>
</document>

More resources

GitHub examples

You may easily run the code above and see the feature in action in our GitHub examples:

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