我尝试在Windows 7上使用WIA 2.0，C＃，。net 4.0从网络摄像头拍照。我尝试了许多不同的样本，但没有任何效果。我总是得到这个异常：“ComException未处理”来自HRESULT的异常：0x80210015“。代码是WIA_S_NO_DEVICE_AVAILABLE。我检查过，如果WIA-Service正在运行，并且凸轮出现在扫描仪和相机中我不知道这里有什么问题！有人可以帮忙吗？
此行引发异常：
设备d = class1.ShowSelectDevice（WiaDeviceType.CameraDeviceType，true，false）;：
这里是代码
string DeviceID;
const string wiaFormatBMP = "{B96B3CAB-0728-11D3-9D7B-0000F81EF32E}";
const string wiaFormatPNG = "{B96B3CAF-0728-11D3-9D7B-0000F81EF32E}";
const string wiaFormatGIF = "{B96B3CB0-0728-11D3-9D7B-0000F81EF32E}";
const string wiaFormatJPEG = "{B96B3CAE-0728-11D3-9D7B-0000F81EF32E}";
const string wiaFormatTIFF = "{B96B3CB1-0728-11D3-9D7B-0000F81EF32E}";
class WIA_DPS_DOCUMENT_HANDLING_SELECT
{
public const uint FEEDER = 0x00000001;
public const uint FLATBED = 0x00000002;
}
class WIA_DPS_DOCUMENT_HANDLING_STATUS
{
public const uint FEED_READY = 0x00000001;
}
class WIA_PROPERTIES
{
public const uint WIA_RESERVED_FOR_NEW_PROPS = 1024;
public const uint WIA_DIP_FIRST = 2;
public const uint WIA_DPA_FIRST = WIA_DIP_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
public const uint WIA_DPC_FIRST = WIA_DPA_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
//
// Scanner only device properties (DPS)
//
public const uint WIA_DPS_FIRST = WIA_DPC_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
public const uint WIA_DPS_DOCUMENT_HANDLING_STATUS = WIA_DPS_FIRST + 13;
public const uint WIA_DPS_DOCUMENT_HANDLING_SELECT = WIA_DPS_FIRST + 14;
}
class WIA_ERRORS
{
public const uint BASE_VAL_WIA_ERROR = 0x80210000;
public const uint WIA_ERROR_PAPER_EMPTY = BASE_VAL_WIA_ERROR + 3;
}
public void ADFScan()
{
//Choose Scanner
CommonDialogClass class1 = new CommonDialogClass();
Device d = class1.ShowSelectDevice(WiaDeviceType.CameraDeviceType, true, false);
if (d != null)
{
this.DeviceID = d.DeviceID;
}
else
{
//no scanner chosen
return;
}
WIA.CommonDialog WiaCommonDialog = new CommonDialogClass();
bool hasMorePages = true;
int x = 0;
int numPages = 0;
while (hasMorePages)
{
//Create DeviceManager
DeviceManager manager = new DeviceManagerClass();
Device WiaDev = null;
foreach (DeviceInfo info in manager.DeviceInfos)
{
if (info.DeviceID == this.DeviceID)
{
WIA.Properties infoprop = null;
infoprop = info.Properties;
//connect to scanner
WiaDev = info.Connect();
break;
}
}
//Start Scan
WIA.ImageFile img = null;
WIA.Item Item = WiaDev.Items[1] as WIA.Item;
try
{
img = (ImageFile)WiaCommonDialog.ShowTransfer(Item, wiaFormatJPEG, false);
//process image:
//one would do image processing here
//
//Save to file
string varImageFileName = "c:\\test" + x.ToString() + ".jpg";
if (File.Exists(varImageFileName))
{
//file exists, delete it
File.Delete(varImageFileName);
}
img.SaveFile(varImageFileName);
numPages++;
img = null;
}
catch (Exception ex)
{
MessageBox.Show("Error: " + ex.Message);
}
finally
{
Item = null;
//determine if there are any more pages waiting
Property documentHandlingSelect = null;
Property documentHandlingStatus = null;
foreach (Property prop in WiaDev.Properties)
{
if (prop.PropertyID == WIA_PROPERTIES.WIA_DPS_DOCUMENT_HANDLING_SELECT)
documentHandlingSelect = prop;
if (prop.PropertyID == WIA_PROPERTIES.WIA_DPS_DOCUMENT_HANDLING_STATUS)
documentHandlingStatus = prop;
}
hasMorePages = false; //assume there are no more pages
if (documentHandlingSelect != null)
//may not exist on flatbed scanner but required for feeder
{
//check for document feeder
if ((Convert.ToUInt32(documentHandlingSelect.get_Value()) & WIA_DPS_DOCUMENT_HANDLING_SELECT.FEEDER) != 0)
{
hasMorePages = ((Convert.ToUInt32(documentHandlingStatus.get_Value()) & WIA_DPS_DOCUMENT_HANDLING_STATUS.FEED_READY) != 0);
}
}
x++;
}
}
}
感谢您的帮助！
答案 0 :(得分：5)
这是来自Microsoft的未记录错误的典型示例...错误代码仅表示未找到任何设备，未连接或未连接 - WIA已识别。
答案 1 :(得分：1)
如果连接了相机，请尝试添加像CameraTest这样的方法进行测试：
bool CameraTest()
{
bool present = false;
try
{
Device d = class1.ShowSelectDevice(WiaDeviceType.CameraDeviceType, true, false);
present = true;
}
catch (Exception ex)
{}
return present;
}
答案 2 :(得分：-1)
尝试以下代码：
class WIAScanner
{
const string wiaFormatBMP = "{B96B3CAB-0728-11D3-9D7B-0000F81EF32E}";
class WIA_DPS_DOCUMENT_HANDLING_SELECT
{
public const uint FEEDER = 0x00000001;
public const uint FLATBED = 0x00000002;
}
class WIA_DPS_DOCUMENT_HANDLING_STATUS
{
public const uint FEED_READY = 0x00000001;
}
class WIA_PROPERTIES
{
public const uint WIA_RESERVED_FOR_NEW_PROPS = 1024;
public const uint WIA_DIP_FIRST = 2;
public const uint WIA_DPA_FIRST = WIA_DIP_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
public const uint WIA_DPC_FIRST = WIA_DPA_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
//
// Scanner only device properties (DPS)
//
public const uint WIA_DPS_FIRST = WIA_DPC_FIRST + WIA_RESERVED_FOR_NEW_PROPS;
public const uint WIA_DPS_DOCUMENT_HANDLING_STATUS = WIA_DPS_FIRST + 13;
public const uint WIA_DPS_DOCUMENT_HANDLING_SELECT = WIA_DPS_FIRST + 14;
}
/// <summary>
/// Use scanner to scan an image (with user selecting the scanner from a dialog).
/// </summary>
/// <returns>Scanned images.</returns>
public static List<Image> Scan()
{
WIA.ICommonDialog dialog = new WIA.CommonDialog();
WIA.Device device = dialog.ShowSelectDevice(WIA.WiaDeviceType.UnspecifiedDeviceType, true, false);
if (device != null)
{
return Scan(device.DeviceID);
}
else
{
throw new Exception("You must select a device for scanning.");
}
}
/// <summary>
/// Use scanner to scan an image (scanner is selected by its unique id).
/// </summary>
/// <param name="scannerName"></param>
/// <returns>Scanned images.</returns>
public static List<Image> Scan(string scannerId)
{
List<Image> images = new List<Image>();
bool hasMorePages = true;
while (hasMorePages)
{
// select the correct scanner using the provided scannerId parameter
WIA.DeviceManager manager = new WIA.DeviceManager();
WIA.Device device = null;
foreach (WIA.DeviceInfo info in manager.DeviceInfos)
{
if (info.DeviceID == scannerId)
{
// connect to scanner
device = info.Connect();
break;
}
}
// device was not found
if (device == null)
{
// enumerate available devices
string availableDevices = "";
foreach (WIA.DeviceInfo info in manager.DeviceInfos)
{
availableDevices += info.DeviceID + "\n";
}
// show error with available devices
throw new Exception("The device with provided ID could not be found. Available Devices:\n" + availableDevices);
}
WIA.Item item = device.Items[1] as WIA.Item;
try
{
// scan image
WIA.ICommonDialog wiaCommonDialog = new WIA.CommonDialog();
WIA.ImageFile image = (WIA.ImageFile)wiaCommonDialog.ShowTransfer(item, wiaFormatBMP, false);
// save to temp file
string fileName = Path.GetTempFileName();
File.Delete(fileName);
image.SaveFile(fileName);
image = null;
// add file to output list
images.Add(Image.FromFile(fileName));
}
catch (Exception exc)
{
throw exc;
}
finally
{
item = null;
//determine if there are any more pages waiting
WIA.Property documentHandlingSelect = null;
WIA.Property documentHandlingStatus = null;
foreach (WIA.Property prop in device.Properties)
{
if (prop.PropertyID == WIA_PROPERTIES.WIA_DPS_DOCUMENT_HANDLING_SELECT)
documentHandlingSelect = prop;
if (prop.PropertyID == WIA_PROPERTIES.WIA_DPS_DOCUMENT_HANDLING_STATUS)
documentHandlingStatus = prop;
}
// assume there are no more pages
hasMorePages = false;
// may not exist on flatbed scanner but required for feeder
if (documentHandlingSelect != null)
{
// check for document feeder
if ((Convert.ToUInt32(documentHandlingSelect.get_Value()) & WIA_DPS_DOCUMENT_HANDLING_SELECT.FEEDER) != 0)
{
hasMorePages = ((Convert.ToUInt32(documentHandlingStatus.get_Value()) & WIA_DPS_DOCUMENT_HANDLING_STATUS.FEED_READY) != 0);
}
}
}
}
return images;
}
/// <summary>
/// Gets the list of available WIA devices.
/// </summary>
/// <returns></returns>
public static List<string> GetDevices()
{
List<string> devices = new List<string>();
WIA.DeviceManager manager = new WIA.DeviceManager();
foreach (WIA.DeviceInfo info in manager.DeviceInfos)
{
devices.Add(info.DeviceID);
}
return devices;
}
}