Esempio n. 1
0
            ///  <summary>
            ///  Creates an event object for the overlapped structure used with 
            ///  ReadFile. Called before the first call to ReadFile.
            ///  </summary>
            ///  
            ///  <param name="hidOverlapped"> the overlapped structure </param>
            ///  <param name="eventObject"> the event object </param>

            public void PrepareForOverlappedTransfer(ref FileIO.OVERLAPPED hidOverlapped, ref SafeWaitHandle eventObject) 
            {                 
                try 
                { 
                    //  ***
                    //  API function: CreateEvent
                    
                    //  Purpose: Creates an event object for the overlapped structure used with ReadFile.
                    
                    //  Accepts:
                    //  A security attributes structure.
                    //  Manual Reset = False (The system automatically resets the state to nonsignaled 
                    //  after a waiting thread has been released.)
                    //  Initial state = True (signaled)
                    //  An event object name (optional)
                    
                    //  Returns: a handle to the event object
                    //  ***

                    eventObject = FileIO.CreateEvent(null, System.Convert.ToInt32(false), System.Convert.ToInt32(true), ""); 
                    
                    //  Debug.WriteLine(MyDebugging.ResultOfAPICall("CreateEvent"))
                    
                    //  Set the members of the overlapped structure.
                    
                    hidOverlapped.Offset = 0; 
                    hidOverlapped.OffsetHigh = 0; 
                    hidOverlapped.hEvent = eventObject; 
                    readyForOverlappedTransfer = true;                     
                } 
                catch ( Exception ex ) 
                { 
                    DisplayException( MODULE_NAME, ex ); 
                    throw ; 
                }                 
            }