Windows图像采集 – 在C＃中设置设备属性

我有一个C＃（WinForm）程序，支持使用WIA进行扫描。 我正在尝试在扫描一个或多个文档之前设置设备属性。 主要是我想设置扫描仪的纸张尺寸。 以下是代码片段：

foreach (Property property in selectedDevice.Properties) { //WiaProperties.WiaDpsHorizontalBedSize is my constant if (property.PropertyID == WiaProperties.WiaDpsHorizontalBedSize) { //Set property value here... } } 

我找到了水平床尺寸属性，但问题是如何将其设置为值？ 有一个属性的set_Value属性，但似乎将ref引用到结果对象。 所以我不知道如何在设备上设置属性？

Answer 1

我正在研究一个扫描项目，而且很少有WIA例子。 此代码是您要设置床大小，DPI等的代码。请查看SetProperty方法，并提供有关如何处理set_Value的示例。

 class Scan { // Scanner only device properties (DPS) public const int WIA_RESERVED_FOR_NEW_PROPS = 1024; public const int WIA_DIP_FIRST = 2; public const int WIA_DPA_FIRST = WIA_DIP_FIRST + WIA_RESERVED_FOR_NEW_PROPS; public const int WIA_DPC_FIRST = WIA_DPA_FIRST + WIA_RESERVED_FOR_NEW_PROPS; public const int WIA_DPS_FIRST = WIA_DPC_FIRST + WIA_RESERVED_FOR_NEW_PROPS; public const int WIA_DPS_DOCUMENT_HANDLING_STATUS = WIA_DPS_FIRST + 13; public const int WIA_DPS_DOCUMENT_HANDLING_SELECT = WIA_DPS_FIRST + 14; public const int FEEDER = 1; public const int FLATBED = 2; public const int DUPLEX = 4; public const int FEED_READY = 1; WIA.CommonDialog _dialog = new WIA.CommonDialog(); WIA.Device _scanner; public void ADFScan() { _dialog = new CommonDialogClass(); _scanner = _dialog.ShowSelectDevice(WIA.WiaDeviceType.ScannerDeviceType, false, false); foreach (Property item in _scanner.Items[1].Properties) { switch (item.PropertyID) { case 6146: //4 is Black-white,gray is 2, color 1 SetProperty(item, 2); break; case 6147: //dots per inch/horizontal SetProperty(item, 100); break; case 6148: //dots per inch/vertical SetProperty(item, 100); break; case 6149: //x point where to start scan SetProperty(item, 0); break; case 6150: //y-point where to start scan SetProperty(item, 0); break; case 6151: //horizontal exent SetProperty(item, (int)(8.5 * 100)); break; case 6152: //vertical extent SetProperty(item, 11 * 100); break; } } ImageFile image = (ImageFile)_scanner.Items[1].Transfer(FormatID.wiaFormatPNG); System.IO.File.Delete("tmp.png"); image.SaveFile("tmp.png"); } private void SetProperty(Property property, int value) { IProperty x = (IProperty)property; Object val = value; x.set_Value(ref val); } public void test() { bool WantsToScan = true; while (WantsToScan) ScanAndSaveOnePage(); } static void Main(string[] args) { new Scan().test(); } }