Search PDF Document Text

PDF Xpress™ supports extracting text content from PDF pages and reporting contextual information for specific words. Use PDF Xpress to report the bounding quadrilaterals and surrounding words for any whole or partial word extracted from the pages of a PDF document.

To search text in a PDF document:

Invoke GetTextFinder to create a TextFinder for a specific page in the PDF document.
Invoke GetText to extract the text content present on that page to use as the search domain.
Locate character offsets in the search domain that correspond to specific search phrase occurrences.
Invoke GetTextMatch to query contextual information about a specific search phrase occurrence.

C# Example	Copy Code
/// This code demonstrates how to search PDF document text /// <summary> /// Search a PDF document for the first occurrence of a search string. /// Match the exact, case-sensitive search phrase and report /// the userspace coordinates of the match. public void SearchText( Document document , String searchPhraseString ) { // For each page in the PDF document for ( Int32 pageIndex = 0 ; pageIndex < document.PageCount ; pageIndex++ ) { // Get the text on the page. String searchDomainString = textFinder.GetText( ) ; // For each occurrence of the search phrase on the page Int32 searchCursor = 0 ; while ( 0 <= searchCursor ) { searchCursor = searchDomainString.IndexOf ( searchPhraseString , searchCursor ) ; if ( 0 <= searchCursor ) { // Request PDF text information for the match. TextMatchOptions whichMatch = new TextMatchOptions( ); whichMatch.BeginTextOffset = searchCursor; whichMatch.EndTextOffset = searchCursor + searchPhraseString.Length - 1; TextMatch textMatch = textFinder.GetTextMatch ( whichMatch ); // Report PDF text match information String locationString = ""; foreach ( Quadrilateral quad in textMatch.BoundingQuadrilaterals ) { locationString += String.Format ( NumberFormatInfo.CurrentInfo , "Userspace quadrilateral: x={0} y={1} w={2} h={3}" + Environment.NewLine , quad.BottomLeft.X , quad.BottomLeft.Y , quad.BottomLeft.X + quad.TopRight.X , quad.BottomLeft.Y + quad.TopRight.Y ) ; } String prettyText = String.Format ( "Matched \"{0}\" on page {1}, context is \"{0}{2}{3}\"\r\n{4}" , textMatch.MatchedText , pageIndex + 1 , textMatch.WordsBefore , textMatch.WordsAfter , locationString ); Console.WriteLine(prettyText); // Advance the search cursor searchCursor++; } } } catch ( PdfXpressLicensingException ) { } // PDF Xpress is not licensed for this feature. catch ( PdfXpressLibraryException ) { } // A problem was encountered. catch ( PdfXpressException ) { } // A problem was encountered finally { if ( null != textFinder ) { textFinder.Dispose( ) ; } } } }

C# Example

Copy Code

/// This code demonstrates how to search PDF document text 
/// <summary>
/// Search a PDF document for the first occurrence of a search string.
/// Match the exact, case-sensitive search phrase and report
/// the userspace coordinates of the match.
public void SearchText( Document document , String searchPhraseString )
{
    // For each page in the PDF document
    for ( Int32 pageIndex = 0
        ; pageIndex < document.PageCount
        ; pageIndex++ )
    {
            // Get the text on the page.
            String searchDomainString       = textFinder.GetText( ) ;
            // For each occurrence of the search phrase on the page
            Int32 searchCursor              = 0 ;
            while ( 0 <= searchCursor )
            {
                searchCursor                = searchDomainString.IndexOf
                                                ( searchPhraseString
                                                , searchCursor
                                                ) ;
                if ( 0 <= searchCursor )
                {
                    // Request PDF text information for the match.
                    TextMatchOptions whichMatch = new TextMatchOptions( );
                    whichMatch.BeginTextOffset  = searchCursor;
                    whichMatch.EndTextOffset    = searchCursor
                                                + searchPhraseString.Length - 1;
                    TextMatch textMatch     = textFinder.GetTextMatch
                                                ( whichMatch );
                    // Report PDF text match information
                    String locationString   = "";
                    foreach ( Quadrilateral quad in textMatch.BoundingQuadrilaterals )
                    {
                        locationString      += String.Format
                                                ( NumberFormatInfo.CurrentInfo
                                                , "Userspace quadrilateral: x={0} y={1} w={2} h={3}" + Environment.NewLine
                                                , quad.BottomLeft.X
                                                , quad.BottomLeft.Y
                                                , quad.BottomLeft.X + quad.TopRight.X 
                                                , quad.BottomLeft.Y + quad.TopRight.Y
                                                ) ;
                    }
                    String prettyText       = String.Format
                                                ( "Matched \"{0}\" on page {1}, context is \"{0}{2}{3}\"\r\n{4}"
                                                , textMatch.MatchedText
                                                , pageIndex + 1
                                                , textMatch.WordsBefore
                                                , textMatch.WordsAfter
                                                , locationString
                                                );
                    Console.WriteLine(prettyText);
                    // Advance the search cursor
                    searchCursor++;
                }
            }
        }
        catch ( PdfXpressLicensingException )   { } // PDF Xpress is not licensed for this feature.
        catch ( PdfXpressLibraryException )     { } // A problem was encountered.
        catch ( PdfXpressException )            { } // A problem was encountered
        finally
        {
            if ( null != textFinder )
            {
                textFinder.Dispose( ) ;
            }
        }
   }
}