Search for encrypted text in QR-code signatures

GroupDocs.Signature provides ability to search over secure QR-code signature with standard or custom encryption. Standard encryption is implemented over class SymmetricEncryption class. Creation of this object expects 3 arguments like encryption algorithm enumeration SymmetricAlgorithmType with one of following values (DES, TripleDES, RC2, Rijndael), string value key and string value salt.

Here are the steps to search for secure QR-code text with standard encryption with GroupDocs.Signature:

Searching for embedded text in QR-code signature

This example shows how to search for secure QR-code signature text.

using (Signature signature = new Signature("QRCodeEncryptedText.pdf"))
    // setup key and pasphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    QrCodeSearchOptions options = new QrCodeSearchOptions()
        // specify special pages to search on
        AllPages = true,
        // specify special QRCode type to search
        EncodeType = QrCodeTypes.QR,
        DataEncryption = encryption
    // search for signatures in document
    List<QrCodeSignature> signatures = signature.Search<QrCodeSignature>(options);
    Console.WriteLine("\nSource document contains following signatures.");
    foreach (var qrCodeSignature in signatures)
        Console.WriteLine("QRCode signature found at page {0} with type {1} and text '{2}'", qrCodeSignature.PageNumber,
            qrCodeSignature.EncodeType.TypeName, qrCodeSignature.Text);

More resources

GitHub Examples

You may easily run the code above and see the feature in action in our GitHub examples:

Free Online App

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

You are welcome to eSign PDF, Word, Excel, PowerPoint documents with free to use online GroupDocs Signature App.