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:

Tag	Description
document	The root tag
section	Represents 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)
p	Represents a text paragraph. Can contain the following attribute: style - the style of paragraph
ul	Represents an unordered list
ol	Represents an ordered list
li	Represents a list item
shape	Represents a shape object.
table	Represents a table
tr	Represents a table row
td	Represents 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:

)

Tag	Description
hyperlink	Represents a hyperlink. Can contain the following attribute: link - URL
strong	Represents a strong emphasis (bold text)
em	Represents a regular emphasis (italic text)
br	Represents 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:

Free online document parser App

Along with full featured .NET library we provide simple, but powerful free Apps.

You are welcome to parse documents and extract data from PDF, DOC, DOCX, PPT, PPTX, XLS, XLSX, Emails and more with our free online Free Online Document Parser App.

Plain text Extract text areas