/// <summary>
/// Handles the UnhandledException event of the AppDomain.CurrentDomain.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="UnhandledExceptionEventArgs"/> instance containing the event data.</param>
private static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
{
System.ComponentModel.LicenseException licenseException = GetLicenseException(e.ExceptionObject);
if (licenseException != null)
{
// show information about licensing exception
MessageBox.Show(string.Format("{0}: {1}", licenseException.GetType().Name, licenseException.Message), "Error", MessageBoxButton.OK, MessageBoxImage.Error);
// open article with information about usage of evaluation license
System.Diagnostics.Process process = new System.Diagnostics.Process();
process.StartInfo.FileName = "https://www.vintasoft.com/docs/vstwain-dotnet/Licensing-Twain-Evaluation.html";
process.StartInfo.UseShellExecute = true;
process.Start();
}
}
/// <summary>
/// Scans images.
/// </summary>
private void scanImagesButton_Click(object sender, EventArgs e)
{
try
{
// disable application UI
scanImagesButton.Enabled = false;
// create TWAIN device manager
using (DeviceManager deviceManager = new DeviceManager(this, this.Handle))
{
try
{
// try to find TWAIN device manager
deviceManager.IsTwain2Compatible = twain2CheckBox.Checked;
}
catch (Exception ex)
{
// show dialog with error message
MessageBox.Show(GetFullExceptionMessage(ex), "TWAIN device manager", MessageBoxButtons.OK, MessageBoxIcon.Error);
return;
}
// if 64-bit TWAIN2 device manager is used
if (IntPtr.Size == 8 && deviceManager.IsTwain2Compatible)
{
if (!InitTwain2DeviceManagerMode(deviceManager))
{
return;
}
}
try
{
// open the device manager
deviceManager.Open();
}
catch (Exception ex)
{
// show dialog with error message
MessageBox.Show(GetFullExceptionMessage(ex), "TWAIN device manager", MessageBoxButtons.OK, MessageBoxIcon.Error);
return;
}
// if devices are NOT found
if (deviceManager.Devices.Count == 0)
{
MessageBox.Show("Devices are not found.");
return;
}
// if device is NOT selected
if (!deviceManager.ShowDefaultDeviceSelectionDialog())
{
MessageBox.Show("Device is not selected.");
return;
}
// get reference to the selected device
_device = deviceManager.DefaultDevice;
// set scan settings
_device.ShowUI = showUiCheckBox.Checked;
_device.ShowIndicators = showIndicatorsCheckBox.Checked;
_device.DisableAfterAcquire = !_device.ShowUI;
_device.CloseAfterModalAcquire = false;
AcquireModalState acquireModalState;
do
{
// synchronously acquire image from device
acquireModalState = _device.AcquireModal();
switch (acquireModalState)
{
case AcquireModalState.ImageAcquired:
// dispose previous bitmap in the picture box
if (pictureBox1.Image != null)
{
pictureBox1.Image.Dispose();
pictureBox1.Image = null;
}
// set a bitmap in the picture box
pictureBox1.Image = _device.AcquiredImage.GetAsBitmap(true);
// dispose an acquired image
_device.AcquiredImage.Dispose();
break;
case AcquireModalState.ScanCanceled:
MessageBox.Show("Scan is canceled.");
break;
case AcquireModalState.ScanFailed:
MessageBox.Show(string.Format("Scan is failed: {0}", _device.ErrorString));
break;
}
}while (acquireModalState != AcquireModalState.None);
// close the device
_device.Close();
_device = null;
// close the device manager
deviceManager.Close();
}
}
catch (TwainException ex)
{
MessageBox.Show(GetFullExceptionMessage(ex));
}
catch (Exception ex)
{
System.ComponentModel.LicenseException licenseException = GetLicenseException(ex);
if (licenseException != null)
{
// show information about licensing exception
MessageBox.Show(string.Format("{0}: {1}", licenseException.GetType().Name, licenseException.Message), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
// open article with information about usage of evaluation license
System.Diagnostics.Process process = new System.Diagnostics.Process();
process.StartInfo.FileName = "https://www.vintasoft.com/docs/vstwain-dotnet/Licensing-Twain-Evaluation.html";
process.StartInfo.UseShellExecute = true;
process.Start();
}
else
{
throw;
}
}
finally
{
// enable application UI
scanImagesButton.Enabled = true;
}
}
