C# Requires Chilkat v11.7.0+

Extract PDF Text to a StringBuilder and Save to a File

See more PDF Text Extraction Examples

Demonstrates ExtractTextSb, which writes the extracted text to a StringBuilder instead of returning it as a JSON string. Use it for large documents. The JSON output still receives the quality report. C#

bool success = false;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  The PDF used in this example is available at long_report.pdf

Chilkat.Pdf pdf = new Chilkat.Pdf();
success = pdf.LoadFile("qa_data/pdf/long_report.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("Number of pages: " + Convert.ToString(pdf.NumPages));

//  ExtractTextSb takes the same operation and options as ExtractText, but the text
//  goes to a StringBuilder.  This avoids building a very large JSON string for
//  documents with many pages.
Chilkat.JsonObject json = new Chilkat.JsonObject();
Chilkat.StringBuilder sbText = new Chilkat.StringBuilder();
Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();

success = pdf.ExtractTextSb("text",json,sbText,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("Extracted " + Convert.ToString(sbText.Length) + " characters.");

//  Save the text to a file.
success = sbText.WriteFile("qa_output/long_report.txt","utf-8",false);
if (success == false) {
    Debug.WriteLine(sbText.LastErrorText);
    return;
}

//  The JSON output does not contain the text, but it still has the quality report.
Debug.WriteLine("Quality: " + jsonOut.StringOf("quality.rating"));
Debug.WriteLine("Pages with no text (need OCR): [" + jsonOut.StringOf("quality.pagesNeedingOcr") + "]");

//  Sample output:

//  Number of pages: 3
//  Extracted 4522 characters.
//  Quality: good
//  Pages with no text (need OCR): []