Search for encrypted text in Metadata signatures

GroupDocs.Signature provides ability to search encrypted Metadata signatures 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 encrypted Metadata signature with standard encryption with GroupDocs.Signature:

Search for encrypted Metadata signature text

This example shows how to search for secure Metadata signature text.

using (Signature signature = new Signature("MetadataEncryptedText.docx"))
{
    // setup key and passphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    MetadataSearchOptions options = new MetadataSearchOptions()
    {
        DataEncryption = encryption
    };
    // search for signatures in document
    List<WordProcessingMetadataSignature> signatures = signature.Search<WordProcessingMetadataSignature>(options);
    Console.WriteLine("\nSource document contains following signatures.");
    // get required metadata signatures
    WordProcessingMetadataSignature mdAuthor = signatures.FirstOrDefault(p => p.Name == "Author");
    if(mdAuthor != null)
    {
        Console.WriteLine("Metadata signature found. Name : {0}. Value: {1}", mdAuthor.Name, mdAuthor.GetData<string>());
    }
    // get required metadata signatures
    WordProcessingMetadataSignature mdDocId = signatures.FirstOrDefault(p => p.Name == "DocumentId");
    if (mdDocId != null)
    {
        Console.WriteLine("Metadata signature found. Name : {0}. Value: {1}", mdDocId.Name, mdDocId.GetData<string>());
    }
}

More resources

GitHub Examples

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

Free Online Apps

Along with the full-featured .NET library, we provide simple but powerful free online apps.

To sign PDF, Word, Excel, PowerPoint, and other documents you can use the online apps from the GroupDocs.Signature App Product Family.