OcrRuntimeFileCallback Delegate

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Document.Writer; 
 
public static void OcrRuntimeFileCallbackExample() 
{ 
   // This example assumes that some or all of the OCR runtime files are copied into "C:\MyDir" folder and simulates 
   // an environment where the runtime files can be obtained through helper methods HasResource and GetResourceStream. 
 
   // Create an OCR engine instance 
   IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD); 
 
   // Install a OCR file runtime handler 
   ocrEngine.RuntimeFileCallback = MyRuntimeFileCallback; 
 
   // Startup the engine 
   ocrEngine.Startup(null, null, null, 
      null /* startupParameters is null*/); 
 
   // Perform OCR operation 
   ocrEngine.AutoRecognizeManager.Run( 
      @"C:\LEADTOOLS22\Resources\Images\ocr1.tif", 
      @"C:\LEADTOOLS22\Resources\Images\out.pdf", 
      DocumentFormat.Pdf, 
      null, 
      null); 
 
   // Shutdown 
   ocrEngine.Shutdown(); 
   // Remove the handler 
   ocrEngine.RuntimeFileCallback = null; 
   // Dispose the engine 
   ocrEngine.Dispose(); 
} 
 
private static RasterExceptionCode MyRuntimeFileCallback(IOcrEngine engine, OcrRuntimeFile runtimeFile) 
{ 
   // Called by the OCR engine for each runtime file operation 
 
   RasterExceptionCode result = RasterExceptionCode.Success; 
 
   // Check the operation: 
   switch (runtimeFile.Mode) 
   { 
      case OcrRuntimeFileMode.Exists: 
         Debug.WriteLine($"MyRuntimeFileCallback does '{runtimeFile.FileName}' exist"); 
         // The engine is checking if a certain file exists, call our HasResource helper 
         if (!HasResource(runtimeFile.FileName)) 
            result = RasterExceptionCode.FileNotFound; 
         break; 
 
      case OcrRuntimeFileMode.Open: 
         Debug.WriteLine($"MyRuntimeFileCallback open '{runtimeFile.FileName}'"); 
         // The engine requested to open the file for reading, call our GetResourceStream helper 
         // and set the Stream property accordingly 
         runtimeFile.Stream = GetResourceStream(runtimeFile.FileName); 
         break; 
 
      case OcrRuntimeFileMode.Close: 
         Debug.WriteLine($"MyRuntimeFileCallback close '{runtimeFile.FileName}'"); 
         // The engine requested to close the file after reading. 
         // Dispose our stream 
         runtimeFile.Stream.Dispose(); 
         break; 
   } 
 
   return result; 
} 
 
private static bool HasResource(string resourceName) 
{ 
   // Do we have this resource? 
   // In our simulation, we will simply check if the file exist on disk 
   // In an Android application, this can check if a resource with this name was embedded 
   return System.IO.File.Exists(Path.Combine(@"C:\MyDir", resourceName)); 
} 
 
private static Stream GetResourceStream(string resourceName) 
{ 
   // Get a stream that can read from resource 
   // In our simulation, we will simply check if the file exist on disk 
   // In an Android application, this can call the appropriate platform API to obtain 
   // a stream to the resource 
   return System.IO.File.OpenRead(Path.Combine(@"C:\MyDir", resourceName)); 
}