Search text in PDF documents

To search a keyword in PDF documents Search(String) method is used. This method returns the collection of SearchResult objects. For details, see Search Text.

Here are the steps to search a keyword in PDF document:

  • Instantiate Parser object for the initial document;
  • Call Search(string) method and obtain the collection of SearchResult objects;
  • Iterate through the collection and get the position and text.

The following example shows how to find a keyword in PDF document:

// Create an instance of Parser class
using(Parser parser = new Parser(filePath))
{
    // Search a keyword:
    IEnumerable<SearchResult> sr = parser.Search("page number");
   
    // Iterate over search results
    foreach(SearchResult s in sr)
    {
        // Print an index and found text:
        Console.WriteLine(string.Format("At {0}: {1}", s.Position, s.Text));
    }
}

Search(String, SearchOptions) is used for the advanced search in PDF documents - like search with regular expressions, search by pages etc. SearchOptions parameter is used to customize a search.

Here are the steps to search with a regular expression in PDF document:

The following example shows how to search with a regular expression in PDF document:

// Create an instance of Parser class
using(Parser parser = new Parser(filePath))
{
    // Search with a regular expression with case matching
    IEnumerable<SearchResult> sr = parser.Search("page number: [0-9]+", new SearchOptions(true, false, true));
    // Iterate over search results
    foreach(SearchResult s in sr)
    {
        // Print an index and found text:
        Console.WriteLine(string.Format("At {0}: {1}", s.Position, s.Text));
    }
}

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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