Search for Text e-signatures

using (Signature signature = new Signature(sample.pdf))
{
    // setup search options
    TextSearchOptions searchOptions = new TextSearchOptions()
    {
        // search only page with specified number
        PageNumber = null,
        // specify as true to search all pages of a document
        AllPages = true,
        // specify text to search
        Text = "JS_",
        // specify text math type
        MatchType = TextMatchType.Contains
    };
    // search document
    List<TextSignature> signatures = signature.Search<TextSignature>(searchOptions);
    // output signatures
    foreach (TextSignature textSignature in signatures)
    {
        if (textSignature != null)
        {
            Console.Write($"Found Text signature: {textSignature.SignatureImplementation} with text {textSignature.Text}.");
            Console.WriteLine($"Location at {textSignature.Left}-{textSignature.Top}. Size is {textSignature.Width}x{textSignature.Height}.");
        }
    }
}