m_SerialPort.WriteToPort((LPCTSTR)m_strEditSendMsg);//发送数据
这句错误。下面是函数原型
void CSerialPort::WriteToPort(char* string)
{        
    assert(m_hComm != 0);
    
    memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
    strcpy(m_szWriteBuffer, string);
    m_nWriteSize=strlen(string);

    // set event for write
    SetEvent(m_hWriteEvent);
}

类型不匹配！你把函数改成这试试
 void CSerialPort::WriteToPort( const char* string)

m_SerialPort[0].WriteToPort((LPCTSTR)strTemp);调用下面那个函数
void CSerialPort::WriteToPort(const char* string)
{        
    assert(m_hComm != 0);
    
    memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
    strcpy(m_szWriteBuffer, string);
    m_nWriteSize=strlen(string);

    // set event for write
    SetEvent(m_hWriteEvent);
}


void CSerialPort::WriteToPort(char* string,int n)
{        
    assert(m_hComm != 0);

    memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
//    memset(m_szWriteBuffer, 0, n);
//    strncpy(m_szWriteBuffer, string, n);
    memcpy(m_szWriteBuffer, string, n);
    m_nWriteSize=n;

    // set event for write
    SetEvent(m_hWriteEvent);
}



void CSerialPort::WriteToPort(LPCTSTR string,int n)
{        
    assert(m_hComm != 0);

    memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
//    strncpy(m_szWriteBuffer, string, n);
    memcpy(m_szWriteBuffer, string, n);
    m_nWriteSize=n;

    // set event for write
    SetEvent(m_hWriteEvent);
}

LPCTSTR  就是const char*

但是开始void CSerialPort::WriteToPort(LPCTSTR string)就是出现问题