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这个程序能够打开串口，能够显示'open the serial port successfully'信息，也能够显示“ok”,但是，问题就出在ShowMessage(pBuffer);这个地方，只能够显示0。
斑竹和各位能不能给我看一下，到底在读串口的时候，问题出在什么地方呢？


谢谢了，源代码如下：
//---------------------------------------------------------------------------

#include
#pragma hdrstop

#include "Unit1.h"
HANDLE hComm;
int (*pCardReady)(long*);
static long pBuffer[100]={0};
COMMTIMEOUTS ctmoNew={0},ctmoOld;
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{  DCB dcbCommPort;

  // OPEN THE COMM PORT.
  // REPLACE "COM1" WITH A STRING OR "COM1", "COM3", ETC. TO OPEN
  // ANOTHER PORT.

  hComm = CreateFile("COM1",
                      GENERIC_READ | GENERIC_WRITE,
                      0,
                      0,
                      OPEN_EXISTING,
                      0,
                      0);

  // IF THE PORT CANNOT BE OPENED, BAIL OUT.

  if(hComm == INVALID_HANDLE_VALUE) Application->Terminate();
  else
  ShowMessage("open the serial port successfully!");

  // SET THE COMM TIMEOUTS IN OUR EXAMPLE.

  GetCommTimeouts(hComm,&ctmoOld);
  ctmoNew.ReadTotalTimeoutConstant = 100;
  ctmoNew.ReadTotalTimeoutMultiplier = 0;
  ctmoNew.WriteTotalTimeoutMultiplier = 0;
  ctmoNew.WriteTotalTimeoutConstant = 0;
  SetCommTimeouts(hComm, &ctmoNew);



  dcbCommPort.DCBlength = sizeof(DCB);
  GetCommState(hComm, &dcbCommPort);
  BuildCommDCB("9600,N,8,1", &dcbCommPort);
  SetCommState(hComm, &dcbCommPort);


 
}

//---------------------------------------------------------------------------

void __fastcall TForm1::Button2Click(TObject *Sender)
{
  DWORD dwBytesRead;


   // TRY TO READ CHARACTERS FROM THE SERIAL PORT.
   // IF THERE ARE NONE, IT WILL TIME OUT AND TRY AGAIN.
   // IF THERE ARE, IT WILL DISPLAY THEM.


     bool rValue=ReadFile(hComm, pBuffer, 50, &dwBytesRead, NULL);
     if(!rValue==NULL)
     {ShowMessage("ok");
     ShowMessage(pBuffer[0]);}
     else
     ShowMessage("no");
}
//---------------------------------------------------------------------------


void __fastcall TForm1::Button3Click(TObject *Sender)
{
CloseHandle(hComm);        
}
//---------------------------------------------------------------------------



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