利用Socket实现CAsynsocket类

CAsynSocket是一个异步socket类，用于实现基于Windows平台下的网络编程。它能够同时处理多个连接请求，并且能够实现非阻塞的网络通信，提高了程序的效率。

下面是利用Socket实现CAsynSocket类的示例代码：

// CAsynSocket.h 文件

#ifndef _CASYN_SOCKET_H_
#define _CASYN_SOCKET_H_

#include <winsock2.h>
#include <string>

class CAsynSocket
{
public:
    CAsynSocket();
    virtual ~CAsynSocket();

    bool Create();
    bool Bind(const std::string& address, const int port);
    bool Listen(const int backlog = 5);
    bool Accept(CAsynSocket& clientSocket);
    bool Connect(const std::string& address, const int port);
    bool Send(const char* data, const int length);
    bool Receive(char* data, const int length);
    void Close();

private:
    SOCKET m_socket;
    bool m_isCreated;
};

#endif


// CAsynSocket.cpp 文件

#include "CAsynSocket.h"

CAsynSocket::CAsynSocket()
{
    m_socket = INVALID_SOCKET;
    m_isCreated = false;
}

CAsynSocket::~CAsynSocket()
{
    Close();
}

bool CAsynSocket::Create()
{
    m_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (m_socket == INVALID_SOCKET)
    {
        return false;
    }
    m_isCreated = true;
    return true;
}

bool CAsynSocket::Bind(const std::string& address, const int port)
{
    if (!m_isCreated)
    {
        return false;
    }

    sockaddr_in sockAddr;
    memset(&sockAddr, 0, sizeof(sockAddr));
    sockAddr.sin_family = AF_INET;
    sockAddr.sin_addr.s_addr = inet_addr(address.c_str());
    sockAddr.sin_port = htons(port);

    int result = bind(m_socket, (sockaddr*)&sockAddr, sizeof(sockAddr));
    if (result == SOCKET_ERROR)
    {
        return false;
    }
    return true;
}

bool CAsynSocket::Listen(const int backlog)
{
    if (!m_isCreated)
    {
        return false;
    }

    int result = listen(m_socket, backlog);
    if (result == SOCKET_ERROR)
    {
        return false;
    }
    return true;
}

bool CAsynSocket::Accept(CAsynSocket& clientSocket)
{
    if (!m_isCreated)
    {
        return false;
    }

    sockaddr_in clientAddr;
    int clientAddrSize = sizeof(clientAddr);
    SOCKET clientSocketHandle = accept(m_socket, (sockaddr*)&clientAddr, &clientAddrSize);
    if (clientSocketHandle == INVALID_SOCKET)
    {
        return false;
    }

    clientSocket.m_socket = clientSocketHandle;
    clientSocket.m_isCreated = true;

    return true;
}

bool CAsynSocket::Connect(const std::string& address, const int port)
{
    if (!m_isCreated)
    {
        return false;
    }

    sockaddr_in sockAddr;
    memset(&sockAddr, 0, sizeof(sockAddr));
    sockAddr.sin_family = AF_INET;
    sockAddr.sin_addr.s_addr = inet_addr(address.c_str());
    sockAddr.sin_port = htons(port);

    int result = connect(m_socket, (sockaddr*)&sockAddr, sizeof(sockAddr));
    if (result == SOCKET_ERROR)
    {
        return false;
    }
    return true;
}

bool CAsynSocket::Send(const char* data, const int length)
{
    if (!m_isCreated)
    {
        return false;
    }

    int result = send(m_socket, data, length, 0);
    if (result == SOCKET_ERROR)
    {
        return false;
    }
    return true;
}

bool CAsynSocket::Receive(char* data, const int length)
{
    if (!m_isCreated)
    {
        return false;
    }

    int result = recv(m_socket, data, length, 0);
    if (result == SOCKET_ERROR)
    {
        return false;
    }
    return true;
}

void CAsynSocket::Close()
{
    if (m_isCreated)
    {
        closesocket(m_socket);
        m_isCreated = false;
    }
}

以上代码实现了CAsynSocket类的基本功能，包括创建socket、绑定地址、监听端口、接受连接、连接远程主机、发送数据和接收数据等。可以根据需要进行扩展。