如何在程序中检测对方摘机。

Question

To： Wally_wu(韦利) ,如何检测呢？

Answer 1

To  hjb8000(北极熊):多谢指教，不过我是个beginner.不知如何检测。

Answer 2

我有源代码，要吗？
最近我也在做这个，摘机是可以判断了，就是声音效果不佳，最后Boss让我放弃了，
我们公司最后决定用语音卡来实现这个功能！

Answer 3

其实也不难，不过下面的程序使用C++BUIDER写的，大致流程：
打开串口，设置串口响应事件时必须设置DCD响应事件
 if ( !SetCommState(FhCom, &dcb) ||
         !SetCommMask(FhCom, EV_RXCHAR  |
                             //EV_BREAK   |
                             //EV_CTS     |
                             //EV_DSR     |
                             //EV_ERR     |
                             //EV_RING    |
                             EV_TXEMPTY   |
                             //EV_RXFLAG  |
                             EV_RLSD     ) ||  在检察串口事件WaitCommEvent(CommHandle, &dwEventMask, &eOverLapped);
判断dwEventMask事件中是否有DCD事件，如果有就给主线程中发消息，在该消息中处理即可
void __fastcall TCommThread::Execute()
{
  DWORD   dwEventMask;
  while(true)  {
    dwEventMask = 0;
    WaitCommEvent(CommHandle, &dwEventMask, &eOverLapped);
    ClearCommError(CommHandle, &ErrWord, &comstat);
    WaitForSingleObject(eOverLapped.hEvent, INFINITE);
    FBytesInQue  = comstat.cbInQue;
    FBytesOutQue = comstat.cbOutQue;
    if ( dwEventMask & EV_TXEMPTY ) {      // Êä³ö»º³åÇø¿Õ
      //PostMessageToThread( Owner->ThreadID, WM_OUTBUFFEREMPTY, 0 ,0L );
      PostMessageToThread( Owner->DataHandleThread->ThreadID, WM_OUTBUFFEREMPTY, 0 ,0L );
    }
    if ( ( dwEventMask & EV_RXCHAR ) && CanInterrupt &&
              ( FBytesInQue >= FRThreshold ) )  {      // ÊäÈ뻺³åÇø½ÓÊÕµ½Ò»×Ö·û
      CanInterrupt = false;
      //PostMessageToThread( Owner->ThreadID, WM_OVERRTHRESHOLD,0,0);
      PostMessageToThread( Owner->DataHandleThread->ThreadID, WM_OVERRTHRESHOLD,0,0);
    }
    if ( (dwEventMask & EV_RLSD )||
         (dwEventMask & EV_BREAK )||
         (dwEventMask & EV_CTS )||
         (dwEventMask & EV_DSR )||
         (dwEventMask & EV_ERR )||
         (dwEventMask & EV_RING )||
         (dwEventMask & EV_RXFLAG ) )
    {
       PostMessageToThread( Owner->DataHandleThread->ThreadID, WM_PHONERING,dwEventMask,0);    //ÕýÔÚÕðÁå
    }
  }     // while
}