Advanced search for QR-code signatures

GroupDocs.Signature provides QrCodeSearchOptions class to specify different options to search for QR-code signatures.

Here are the steps to search for barcode signatures within the document with GroupDocs.Signature:

This example shows how to make advanced search for QR-code signature in the document with enabled options of grabbing QR-code image content.

using (Signature signature = new Signature("sample.pdf"))
    QrCodeSearchOptions options = new QrCodeSearchOptions()
        // specify special pages to search on
        AllPages = false,
        PageNumber = 1,
        PagesSetup = new PagesSetup() { FirstPage = true, LastPage = true, OddPages = false, EvenPages = false },
        // specify special QRCode type to search
        EncodeType = QrCodeTypes.Aztec,
        // specify text match type
        MatchType = TextMatchType.Contains,
        // specify text pattern to search
        Text = "John",
        // set field for QRCode images returning
        ReturnContent = true,
        // specify type of returned QRCode images
        ReturnContentType = FileType.PNG
    // search for signatures in document
    List<QrCodeSignature> signatures = signature.Search<QrCodeSignature>(options); //For evaluation version is 0
    Console.WriteLine("\nSource document contains following signatures.");
    foreach (QrCodeSignature qrCodeSignature in signatures)
        Console.WriteLine("QRCode signature found at page {0} with type {1} and text {2}", qrCodeSignature.PageNumber, qrCodeSignature.EncodeType, qrCodeSignature.Text);
        Console.WriteLine("QRCode signature size {0} and format {1}", qrCodeSignature.Content?.Length, qrCodeSignature.Format);
        Console.WriteLine($"Location at {qrCodeSignature.Left}-{qrCodeSignature.Top}. Size is {qrCodeSignature.Width}x{qrCodeSignature.Height}.");
    //Save QRCode images
    string outputPath = System.IO.Path.Combine(Constants.OutputPath, "SearchForQRCodeAdvanced");
    if (!Directory.Exists(outputPath))
    int i = 0;
    foreach (QrCodeSignature qrCodeSignature in signatures)
        string outputFilePath = System.IO.Path.Combine(outputPath, $"image{i}{qrCodeSignature.Format.Extension}");
        using (FileStream fs = new FileStream(outputFilePath, FileMode.Create))
            fs.Write(qrCodeSignature.Content, 0, qrCodeSignature.Content.Length);

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.