test.cs

using (TXTextControl.ServerTextControl tx = new TXTextControl.ServerTextControl())
{
    tx.Create();

    TXTextControl.LoadSettings ls = new TXTextControl.LoadSettings()
    {
        PDFImportSettings = TXTextControl.PDFImportSettings.GenerateParagraphs
    };

    // load PDF document
    tx.Load("App_Data/sample.pdf", TXTextControl.StreamType.AdobePDF, ls);
    
    // retrieve plain text
    var text = tx.Text;

    Console.WriteLine(text);
}