private WiaState InitWia()
{
var device = WiaApi.GetDevice(scanDevice);
var item = WiaApi.GetItem(device, settings);
WiaApi.Configure(device, item, settings);
return(new WiaState(device, item));
}
protected override IEnumerable <ScannedImage> ScanInternal()
{
using (var eventLoop = new WiaBackgroundEventLoop(ScanProfile, ScanDevice, threadFactory))
{
bool supportsFeeder = eventLoop.GetSync(wia => WiaApi.DeviceSupportsFeeder(wia.Device));
if (ScanProfile.PaperSource != ScanSource.Glass && !supportsFeeder)
{
throw new NoFeederSupportException();
}
bool supportsDuplex = eventLoop.GetSync(wia => WiaApi.DeviceSupportsDuplex(wia.Device));
if (ScanProfile.PaperSource == ScanSource.Duplex && !supportsDuplex)
{
throw new NoDuplexSupportException();
}
int pageNumber = 1;
int retryCount = 0;
bool retry = false;
bool cancel = false;
do
{
ScannedImage image;
try
{
if (pageNumber > 1 && ScanProfile.WiaDelayBetweenScans)
{
int delay = (int)(ScanProfile.WiaDelayBetweenScansSeconds.Clamp(0, 30) * 1000);
Thread.Sleep(delay);
}
image = TransferImage(eventLoop, pageNumber, out cancel);
pageNumber++;
retryCount = 0;
retry = false;
}
catch (ScanDriverException e)
{
if (ScanProfile.WiaRetryOnFailure && e.InnerException is COMException &&
(uint)((COMException)e.InnerException).ErrorCode == 0x80004005 && retryCount < MAX_RETRIES)
{
Thread.Sleep(1000);
retryCount += 1;
retry = true;
continue;
}
throw;
}
catch (Exception e)
{
throw new ScanDriverUnknownException(e);
}
if (image != null)
{
yield return(image);
}
} while (retry || (!cancel && ScanProfile.PaperSource != ScanSource.Glass));
}
}
protected override async Task ScanInternal(ScannedImageSource.Concrete source)
{
using (var eventLoop = new WiaBackgroundEventLoop(ScanProfile, ScanDevice))
{
bool supportsFeeder = eventLoop.GetSync(wia => WiaApi.DeviceSupportsFeeder(wia.Device));
if (ScanProfile.PaperSource != ScanSource.Glass && !supportsFeeder)
{
throw new NoFeederSupportException();
}
bool supportsDuplex = eventLoop.GetSync(wia => WiaApi.DeviceSupportsDuplex(wia.Device));
if (ScanProfile.PaperSource == ScanSource.Duplex && !supportsDuplex)
{
throw new NoDuplexSupportException();
}
int pageNumber = 1;
int retryCount = 0;
bool retry = false;
bool done = false;
do
{
ScannedImage image;
try
{
if (pageNumber > 1 && ScanProfile.WiaDelayBetweenScans)
{
int delay = (int)(ScanProfile.WiaDelayBetweenScansSeconds.Clamp(0, 30) * 1000);
Thread.Sleep(delay);
}
(image, done) = await TransferImage(eventLoop, pageNumber);
pageNumber++;
retryCount = 0;
retry = false;
}
catch (ScanDriverException e)
{
if (ScanProfile.WiaRetryOnFailure && e.InnerException is COMException comError &&
(uint)comError.ErrorCode == 0x80004005 && retryCount < MAX_RETRIES)
{
Thread.Sleep(1000);
retryCount += 1;
retry = true;
continue;
}
throw;
}
if (image != null)
{
source.Put(image);
}
} while (!CancelToken.IsCancellationRequested && (retry || !done && ScanProfile.PaperSource != ScanSource.Glass));
}
}
protected override IEnumerable <ScannedImage> ScanInternal()
{
using (var eventLoop = new WiaBackgroundEventLoop(ScanProfile, ScanDevice, threadFactory))
{
bool supportsFeeder = eventLoop.GetSync(wia => WiaApi.DeviceSupportsFeeder(wia.Device));
if (ScanProfile.PaperSource != ScanSource.Glass && !supportsFeeder)
{
throw new NoFeederSupportException();
}
bool supportsDuplex = eventLoop.GetSync(wia => WiaApi.DeviceSupportsDuplex(wia.Device));
if (ScanProfile.PaperSource == ScanSource.Duplex && !supportsDuplex)
{
throw new NoDuplexSupportException();
}
int pageNumber = 1;
int retryCount = 0;
bool retry = false;
bool cancel = false;
do
{
ScannedImage image;
try
{
image = TransferImage(eventLoop, pageNumber, out cancel);
pageNumber++;
Debug.WriteLine("Succeeded with retry count {0}", retryCount);
retryCount = 0;
retry = false;
}
catch (ScanDriverException e)
{
if (e.InnerException is COMException && (uint)((COMException)e.InnerException).ErrorCode == 0x80004005 && retryCount < 10)
{
Thread.Sleep(1000);
retryCount += 1;
Debug.WriteLine("Retrying {0}", retryCount);
retry = true;
continue;
}
throw;
}
catch (Exception e)
{
throw new ScanDriverUnknownException(e);
}
if (image != null)
{
yield return(image);
}
} while (retry || (!cancel && ScanProfile.PaperSource != ScanSource.Glass));
}
}
private Stream DoTransfer(int pageNumber, WiaBackgroundEventLoop eventLoop, string format)
{
var invoker = (FormBase)DialogParent;
if (eventLoop.GetSync(wia => wia.Item) == null)
{
return(null);
}
if (ScanParams.NoUI)
{
return(eventLoop.GetSync(wia => WiaApi.Transfer(wia, format, false)));
}
if (pageNumber == 1)
{
// The only downside of the common dialog is that it steals focus.
// If this is the first page, then the user has just pressed the scan button, so that's not
// an issue and we can use it and get the benefits of progress display and immediate cancellation.
return(ScanParams.Modal
? eventLoop.GetSync(wia => invoker.InvokeGet(() => WiaApi.Transfer(wia, format, true)))
: eventLoop.GetSync(wia => WiaApi.Transfer(wia, format, true)));
}
// For subsequent pages, we don't want to take focus in case the user has switched applications,
// so we use the custom form.
var form = formFactory.Create <FScanProgress>();
var waitHandle = new AutoResetEvent(false);
form.PageNumber = pageNumber;
form.Transfer = () => eventLoop.GetSync(wia => WiaApi.Transfer(wia, format, false));
form.Closed += (sender, args) => waitHandle.Set();
if (ScanParams.Modal)
{
invoker.Invoke(() => form.ShowDialog(DialogParent));
}
else
{
invoker.Invoke(() => form.Show(DialogParent));
}
waitHandle.WaitOne();
if (form.Exception != null)
{
WiaApi.ThrowDeviceError(form.Exception);
}
if (form.DialogResult == DialogResult.Cancel)
{
return(null);
}
return(form.ImageStream);
}
protected override IEnumerable <IScannedImage> ScanInternal()
{
using (var eventLoop = new WiaBackgroundEventLoop(ScanSettings, ScanDevice))
{
bool supportsFeeder = eventLoop.GetSync(wia => WiaApi.DeviceSupportsFeeder(wia.Device));
if (ScanSettings.PaperSource != ScanSource.Glass && !supportsFeeder)
{
throw new NoFeederSupportException();
}
int pageNumber = 1;
while (true)
{
bool feederReady = eventLoop.GetSync(wia => WiaApi.DeviceFeederReady(wia.Device));
if (ScanSettings.PaperSource != ScanSource.Glass && !feederReady)
{
if (pageNumber == 1)
{
throw new NoPagesException();
}
break;
}
IScannedImage image;
try
{
image = TransferImage(eventLoop, pageNumber++);
}
catch (ScanDriverException)
{
throw;
}
catch (Exception e)
{
throw new ScanDriverUnknownException(e);
}
if (image == null)
{
break;
}
yield return(image);
if (ScanSettings.PaperSource == ScanSource.Glass)
{
break;
}
}
}
}
protected override IEnumerable <ScannedImage> ScanInternal()
{
using (var eventLoop = new WiaBackgroundEventLoop(ScanProfile, ScanDevice, threadFactory))
{
bool supportsFeeder = eventLoop.GetSync(wia => WiaApi.DeviceSupportsFeeder(wia.Device));
if (ScanProfile.PaperSource != ScanSource.Glass && !supportsFeeder)
{
throw new NoFeederSupportException();
}
bool supportsDuplex = eventLoop.GetSync(wia => WiaApi.DeviceSupportsDuplex(wia.Device));
if (ScanProfile.PaperSource == ScanSource.Duplex && !supportsDuplex)
{
throw new NoDuplexSupportException();
}
int pageNumber = 1;
bool cancel;
do
{
ScannedImage image;
try
{
image = TransferImage(eventLoop, pageNumber++, out cancel);
}
catch (ScanDriverException)
{
throw;
}
catch (Exception e)
{
throw new ScanDriverUnknownException(e);
}
if (image != null)
{
yield return(image);
}
} while (!cancel && ScanProfile.PaperSource != ScanSource.Glass);
}
}
public Stream Transfer(int pageNumber, WiaBackgroundEventLoop eventLoop, string format)
{
if (eventLoop.GetSync(wia => wia.Item) == null)
{
return(null);
}
if (pageNumber == 1)
{
// The only downside of the common dialog is that it steals focus.
// If this is the first page, then the user has just pressed the scan button, so that's not
// an issue and we can use it and get the benefits of progress display and immediate cancellation.
ImageFile imageFile = eventLoop.GetSync(wia =>
(ImageFile) new CommonDialogClass().ShowTransfer(wia.Item, format));
if (imageFile == null)
{
return(null);
}
return(new MemoryStream((byte[])imageFile.FileData.get_BinaryData()));
}
// For subsequent pages, we don't want to take focus in case the user has switched applications,
// so we use the custom form.
var form = formFactory.Create <FScanProgress>();
form.PageNumber = pageNumber;
form.EventLoop = eventLoop;
form.Format = format;
form.ShowDialog();
if (form.Exception != null)
{
WiaApi.ThrowDeviceError(form.Exception);
}
if (form.DialogResult == DialogResult.Cancel)
{
return(null);
}
return(form.ImageStream);
}
public void DoSync(Action <WiaState> action)
{
Exception error = null;
form.Invoke(new Action(() =>
{
try
{
if (wiaState == null)
{
wiaState = InitWia();
}
action(wiaState);
}
catch (Exception ex)
{
error = ex;
}
}));
if (error != null)
{
WiaApi.ThrowDeviceError(error);
}
}
protected override ScanDevice PromptForDeviceInternal()
{
return(WiaApi.PromptForDevice());
}
protected override List <ScanDevice> GetDeviceListInternal()
{
return(WiaApi.GetScanDeviceList());
}
protected override List <ScanDevice> GetDeviceListInternal() => WiaApi.GetScanDeviceList();
protected override ScanDevice PromptForDeviceInternal() => WiaApi.PromptForScanDevice();