How Can I Extract Non-English Text from PDFs using iTextSharp and Handle Encoding Issues?

Using iTextSharp in C# to Extract PDF Content: Addressing Non-English Character Issues

This article tackles the challenge of extracting non-English text from PDF files using iTextSharp in C#. The problem often manifests as garbled text when dealing with languages like Persian or Arabic.

Understanding the Problem's Origin

The root cause lies in an unnecessary encoding conversion:

currentText = Encoding.UTF8.GetString(Encoding.Convert(Encoding.Default, Encoding.UTF8, Encoding.UTF8.GetBytes(currentText)));

This code converts the text to a UTF-8 byte array and then back to a UTF-8 string—a redundant process that inadvertently corrupts characters outside the basic ASCII range (0-127).

The Solution: Simplified Encoding

The solution is straightforward: remove the redundant encoding step. The corrected code is:

public string ReadPdfFile(string fileName) {
    StringBuilder text = new StringBuilder();

    if (File.Exists(fileName)) {
        PdfReader pdfReader = new PdfReader(fileName);

        // ... (rest of the code remains unchanged) ...
    }
    return text.ToString();
}

Further Points to Note

For proper display, verify your application's rendering engine supports Unicode. Using the latest iTextSharp version (currently 5.2.0.0) is recommended for optimal performance.

Handling Right-to-Left Text

While the corrected code resolves encoding issues, right-to-left languages (like Arabic and Hebrew) may still present a challenge. The extracted text might appear in the wrong order. This appears to be a limitation of the PDF format itself, and manual reordering might be necessary depending on the specific language.

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