ntwain/samples/WinConsole32/Program.cs

using NTwain;
using NTwain.Data;
using System.Diagnostics;

namespace WinConsole32
{
    internal class Program
    {
        static async Task Main(string[] args)
        {
            var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).ProductVersion;
            Console.WriteLine($"Console sample {(TWPlatform.Is32bit ? " 32bit" : " 64bit")} on NTwain {libVer}");

            TwainAppSession session = new TwainAppSession();

            session.StateChanged += Session_StateChanged;
            session.SourceDisabled += Session_SourceDisabled1;
            session.Transferred += Session_Transferred;

            var sts = await session.OpenDSMAsync();

            if (sts.IsSuccess)
            {
                Console.WriteLine("Available data sources:");

                TW_IDENTITY_LEGACY firstSrc = default;
                foreach (var src in session.GetSources())
                {
                    if (!firstSrc.HasValue) firstSrc = src;
                    Console.WriteLine($"\t{src}");
                }
                Console.WriteLine();

                var defaultSrc = session.DefaultSource;
                Console.WriteLine($"Default data source = {defaultSrc}");
                Console.WriteLine();

                session.ShowUserSelect();
                Console.WriteLine($"Selected data source = {session.DefaultSource}");
                Console.WriteLine();

                var targetSrc = defaultSrc.HasValue ? defaultSrc : firstSrc;

                if (targetSrc.HasValue)
                {
                    TestThisSource(session, targetSrc);
                }
                else
                {
                    Console.WriteLine("No data source to test.");
                    Console.WriteLine();
                }

                Console.WriteLine("---------------------------------------------");
                Console.WriteLine("Test in progress, press Enter to stop testing");
                Console.WriteLine("---------------------------------------------");
                Console.ReadLine();
                session.TryStepdown(STATE.S1);
            }
            else
            {
                Console.WriteLine("Failed to attach: " + sts);
            }

            Console.WriteLine("-------------------");
            Console.WriteLine("Press Enter to exit");
            Console.WriteLine("-------------------");
            Console.ReadLine();
        }

        static int xferCount = 0;
        static Stopwatch watch;
        private static void Session_Transferred(TwainAppSession sender, TransferredEventArgs e)
        {
            if (e.Data != null)
            {
                var saveFile = $"twain_{DateTime.Now:yyyyMMdd_HHmmss}_{xferCount}";
                Console.WriteLine("SUCCESS! Got twain data #{0} on thread {1}, saving to {saveFile}.", ++xferCount, Environment.CurrentManagedThreadId, saveFile);

                using (var img = new ImageMagick.MagickImage(e.Data.AsStream()))
                {
                    var format = ImageMagick.MagickFormat.Png;
                    if (img.ColorType == ImageMagick.ColorType.Palette)
                    {
                        // bw or gray
                        saveFile += ".png";
                    }
                    else
                    {
                        // color
                        saveFile += ".jpg";
                        format = ImageMagick.MagickFormat.Jpeg;
                        img.Settings.Compression = ImageMagick.CompressionMethod.JPEG;
                        img.Quality = (uint)85;
                    }
                    img.Write(saveFile, format);
                }
            }
            else
            {
                Console.WriteLine("BUMMER! No twain data #{0} on thread {1}.", ++xferCount, Environment.CurrentManagedThreadId);
            }
            e.Dispose();
        }

        private static void Session_StateChanged(TwainAppSession sender, STATE e)
        {
            Console.WriteLine($"Session state changed to {sender.State}");
        }

        private static void Session_SourceDisabled1(TwainAppSession sender, TW_IDENTITY_LEGACY e)
        {
            watch.Stop();
            var elapsed = watch.Elapsed;
            Console.WriteLine($"Session source disabled, took {elapsed}.");
            sender.CloseSource();
        }

        private static void TestThisSource(TwainAppSession session, TW_IDENTITY_LEGACY source)
        {
            Console.WriteLine($"Testing data source {source}");
            Console.WriteLine();

            session.OpenSource(source);

            session.Caps.ICAP_PIXELTYPE.Set(TWPT.RGB);
            session.Caps.ICAP_XRESOLUTION.Set(300f);
            session.Caps.ICAP_YRESOLUTION.Set(300f);
            session.Caps.CAP_XFERCOUNT.Set(100);

            xferCount = 0;
            watch = Stopwatch.StartNew();
            var rc = session.EnableSource(true, false);
        }
    }
}