教程 | 无连接套接字类CxUdpSocket

CxUdpSocket的使用如下(以某个叫做CSomeClass的类的相关代码为例):

一、声明无连接套接字对象实例。

CxUdpSocket m_usRemoteHost;

二、设置无连接套接字事件通知方式。消息响应或回调函数,任选其一。无连接套接字事件有:缓冲区有数据可接收。

void CSomeClass::PreSubclassWindow() 
{
    // TODO: Add your specialized code here and/or call the base class
    HWND hwnd = GetSafeHwnd();
    MSG msg = {hwnd, WM_SOCKET_EVENT};
    m_usRemoteHost.SetWindowMessage(&msg);
    m_csRemoteHost.SetWindowMessage(&msg);
    m_ssLocalHost.SetWindowMessage(&msg);

    if (m_btCSMode == CSM_SERVER)
        ListenRemoteHost();

    CStatic::PreSubclassWindow();
}

三、绑定无连接套接字

BOOL CSomeClass::BindToLocalHost()
{
    if (m_usRemoteHost.IsBinded())
        m_usRemoteHost.Disbind();
        
    BOOL bRet = m_usRemoteHost.Bind(m_nUdpPort);

    CString str;
    if (!bRet)
        str.Format("Bind to %d failed. err code [%d].\n", m_nUdpPort,
                    CxSocket::WSAGetLastError());
    else
        str.Format("Bind to %d succeed.\n", m_nUdpPort);
    OutputDebugString(str);

    return bRet;
}

四、处理消息响应或函数回调。
1.消息响应

BEGIN_MESSAGE_MAP(CSomeClass, CStatic)
    //{{AFX_MSG_MAP(CSomeClass)
    ON_WM_DESTROY()
    //}}AFX_MSG_MAP
    ON_MESSAGE(WM_SOCKET_EVENT, OnSocketEvent)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CSomeClass message handlers
LRESULT CSomeClass::OnSocketEvent(WPARAM wParam, LPARAM lParam) {
if (WSAGETSELECTERROR(lParam) != 0) return 1; int nEvent = WSAGETSELECTEVENT(lParam); switch (nEvent) {
     case FD_ACCEPT: OnSocketAccept(wParam); break;
      
case FD_CLOSE: OnSocketClose(wParam); break;
      
case FD_READ: OnSocketRead(wParam); break;
     default: break; } return 1; } void CSomeClass::OnSocketRead(WPARAM wParam) { if (m_usRemoteHost.GetSocket() == (SOCKET)wParam) { SOME_DATA_STRUCT data = {0}; char szIPAddr[MAX_IPV6] = {'\0'}; if (m_usRemoteHost.RecvFrom(szIPAddr, (LPBYTE)&data, sizeof(data))) {
    //do something with data;

     } } }

2.回调函数

LRESULT CALLBACK CSomeClass::SocketProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    LRESULT lRet = 0;
    CSomeClass* pThis = (CSomeClass*)hwnd;
    if (pThis != NULL)
        lRet = pThis->OnSocketEvent(wParam, lParam);

    return lRet;
}

注意,在使用回调函数时应设置无连接套接字接收缓冲区事件通知方式为回调函数,并且设法把this指针传入设置函数,方便在回调函数中调用成员函数。

MSG msg = {(HWND)this, WM_SOCKET_EVENT};
m_usRemoteHost.SetWindowMessage(&msg, SocketProc);

五、解绑定无连接套接字。

void CSomeClass::OnDestroy() 
{
    CStatic::OnDestroy();
    
    // TODO: Add your message handler code here
    TerminateWaitComm();

    m_csRemoteHost.DisConnect();
    m_ssLocalHost.DisListen();
    m_usRemoteHost.Disbind();
}

  至于无连接套接字数据发送,很简单,在需要处调用以下函数:

m_usRemoteHost.Send((LPBYTE)pData, sizeof(SOME_DATA_STRUCT));

  精练的代码不需要过多解释,你们懂的。To be continued...

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libComm - v1.2 For WinXP/Win7

posted @ 2013-07-27 00:30  凤凰座一辉  阅读(...)  评论(...编辑  收藏