我在 mfc 中有一个客户端服务器应用程序，它向服务器发送消息（字符串），服务器接收消息，并在文本框中显示客户端使用的端口的 IP 地址。我尝试在另一台计算机上运行客户端 exe 文件，但我收到一条错误消息，提示无法连接到服务器。我运行了调试和发布 exe 文件，所以我认为问题出在代码的某个地方。
客户端代码：
#include "stdafx.h"
#include "SocketTestClient.h"
#include "SocketTestClientDlg.h"
#include <string>
#ifdef _DEBUG
#define new DEBUG_NEW
#endif
// CAboutDlg dialog used for App About
class CAboutDlg : public CDialog
{
public:
CAboutDlg();
// Dialog Data
enum { IDD = IDD_ABOUTBOX };
protected:
virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV support
// Implementation
protected:
DECLARE_MESSAGE_MAP()
};
CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
}
void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
CDialog::DoDataExchange(pDX);
}
BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
END_MESSAGE_MAP()
// CSocketTestClientDlg dialog
CSocketTestClientDlg::CSocketTestClientDlg(CWnd* pParent /*=NULL*/)
: CDialog(CSocketTestClientDlg::IDD, pParent)
, m_senddata(_T(""))
, m_recvData(_T(""))
{
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}
void CSocketTestClientDlg::DoDataExchange(CDataExchange* pDX)
{
CDialog::DoDataExchange(pDX);
DDX_Text(pDX, IDC_EDIT2, m_senddata);
DDX_Text(pDX, IDC_EDIT1, m_recvData);
}
BEGIN_MESSAGE_MAP(CSocketTestClientDlg, CDialog)
ON_WM_SYSCOMMAND()
ON_WM_PAINT()
ON_WM_QUERYDRAGICON()
//}}AFX_MSG_MAP
ON_BN_CLICKED(IDOK, &CSocketTestClientDlg::OnBnClickedOk)
ON_BN_CLICKED(IDCANCEL, &CSocketTestClientDlg::OnBnClickedCancel)
END_MESSAGE_MAP()
// CSocketTestClientDlg message handlers
BOOL CSocketTestClientDlg::OnInitDialog()
{
CDialog::OnInitDialog();
// Add "About..." menu item to system menu.
// IDM_ABOUTBOX must be in the system command range.
ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
ASSERT(IDM_ABOUTBOX < 0xF000);
CMenu* pSysMenu = GetSystemMenu(FALSE);
if (pSysMenu != NULL)
{
CString strAboutMenu;
strAboutMenu.LoadString(IDS_ABOUTBOX);
if (!strAboutMenu.IsEmpty())
{
pSysMenu->AppendMenu(MF_SEPARATOR);
pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
}
}
// Set the icon for this dialog. The framework does this automatically
// when the application's main window is not a dialog
SetIcon(m_hIcon, TRUE); // Set big icon
SetIcon(m_hIcon, FALSE); // Set small icon
// TODO: Add extra initialization here
return TRUE; // return TRUE unless you set the focus to a control
}
void CSocketTestClientDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
if ((nID & 0xFFF0) == IDM_ABOUTBOX)
{
CAboutDlg dlgAbout;
dlgAbout.DoModal();
}
else
{
CDialog::OnSysCommand(nID, lParam);
}
}
// If you add a minimize button to your dialog, you will need the code below
// to draw the icon. For MFC applications using the document/view model,
// this is automatically done for you by the framework.
void CSocketTestClientDlg::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CDialog::OnPaint();
}
}
// The system calls this function to obtain the cursor to display while the user drags
// the minimized window.
HCURSOR CSocketTestClientDlg::OnQueryDragIcon()
{
return static_cast<HCURSOR>(m_hIcon);
}
void CSocketTestClientDlg::OnBnClickedOk()
{
SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(s == -1)
{
AfxMessageBox("Socket Initialiation Error");
}
SOCKADDR_IN serveraddr;
struct hostent *hostentry;
bool bSent = false;
std::string server = "10.13.32.133";
int portno = 1818;
hostentry = gethostbyname(server.c_str());
char *pipaddr = inet_ntoa (*(struct in_addr *)*hostentry->h_addr_list);
memset(&serveraddr,0, sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_port = htons(portno);
serveraddr.sin_addr.s_addr = inet_addr(pipaddr);
//serv_addr.sa_data = htons(portno);
if (connect(s,(SOCKADDR*)&serveraddr,sizeof(SOCKADDR_IN)) < 0)
{
AfxMessageBox("ERROR connecting to the server");
exit(1);
}
char sbuf[1024], rbuf[1024];
UpdateData(TRUE);
sprintf(sbuf,"%s\r\n", (const char*) m_senddata);
if(send(s, sbuf, strlen(sbuf), 0) == strlen(sbuf))
{
recv(s, rbuf, 1024, 0);
m_recvData = rbuf;
UpdateData(FALSE);
}
::closesocket(s);
}
void CSocketTestClientDlg::OnBnClickedCancel()
{
OnCancel();
}
服务器代码：
#include "stdafx.h"
#include "SocketTestServer.h"
#include "SocketTestServerDlg.h"
#include <process.h>
#include <string>
#include <sys/types.h>
#ifdef _DEBUG
#define new DEBUG_NEW
#endif
// CAboutDlg dialog used for App About
class CAboutDlg : public CDialog
{
public:
CAboutDlg();
// Dialog Data
enum { IDD = IDD_ABOUTBOX };
protected:
virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV support
// Implementation
protected:
DECLARE_MESSAGE_MAP()
};
CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
}
void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
CDialog::DoDataExchange(pDX);
}
BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
END_MESSAGE_MAP()
// CSocketTestServerDlg dialog
CSocketTestServerDlg::CSocketTestServerDlg(CWnd* pParent /*=NULL*/)
: CDialog(CSocketTestServerDlg::IDD, pParent)
, m_recvData(_T(""))
{
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}
void CSocketTestServerDlg::DoDataExchange(CDataExchange* pDX)
{
CDialog::DoDataExchange(pDX);
DDX_Text(pDX, IDC_EDIT1, m_recvData);
}
BEGIN_MESSAGE_MAP(CSocketTestServerDlg, CDialog)
ON_WM_SYSCOMMAND()
ON_WM_PAINT()
ON_WM_QUERYDRAGICON()
//}}AFX_MSG_MAP
ON_BN_CLICKED(IDOK, &CSocketTestServerDlg::OnBnClickedOk)
ON_WM_TIMER()
ON_BN_CLICKED(IDCANCEL, &CSocketTestServerDlg::OnBnClickedCancel)
END_MESSAGE_MAP()
// CSocketTestServerDlg message handlers
BOOL CSocketTestServerDlg::OnInitDialog()
{
CDialog::OnInitDialog();
// Add "About..." menu item to system menu.
// IDM_ABOUTBOX must be in the system command range.
ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
ASSERT(IDM_ABOUTBOX < 0xF000);
CMenu* pSysMenu = GetSystemMenu(FALSE);
if (pSysMenu != NULL)
{
CString strAboutMenu;
strAboutMenu.LoadString(IDS_ABOUTBOX);
if (!strAboutMenu.IsEmpty())
{
pSysMenu->AppendMenu(MF_SEPARATOR);
pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
}
}
// Set the icon for this dialog. The framework does this automatically
// when the application's main window is not a dialog
SetIcon(m_hIcon, TRUE); // Set big icon
SetIcon(m_hIcon, FALSE); // Set small icon
StartServer();
return TRUE; // return TRUE unless you set the focus to a control
}
void CSocketTestServerDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
if ((nID & 0xFFF0) == IDM_ABOUTBOX)
{
CAboutDlg dlgAbout;
dlgAbout.DoModal();
}
else
{
CDialog::OnSysCommand(nID, lParam);
}
}
// If you add a minimize button to your dialog, you will need the code below
// to draw the icon. For MFC applications using the document/view model,
// this is automatically done for you by the framework.
void CSocketTestServerDlg::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CDialog::OnPaint();
}
}
// The system calls this function to obtain the cursor to display while the user drags
// the minimized window.
HCURSOR CSocketTestServerDlg::OnQueryDragIcon()
{
return static_cast<HCURSOR>(m_hIcon);
}
void CSocketTestServerDlg::StartServer()
{
SOCKADDR_IN serveraddr;
int portno = 1818;
memset(&serveraddr,0, sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_port = htons(portno);
serveraddr.sin_addr.s_addr = INADDR_ANY;
m_serversocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(m_serversocket == -1)
{
AfxMessageBox("Socket Initialiation Error");
}
if(bind(m_serversocket, (SOCKADDR*)&serveraddr,sizeof(SOCKADDR_IN)) < 0)
{
AfxMessageBox("ERROR binding in the server socket");
exit(1);
}
if(listen(m_serversocket,0) < 0)
{
AfxMessageBox("ERROR listening in the server socket");
exit(1);
}
SetTimer(0x01, 100, NULL);
}
static void f(void *p)
{
CSocketTestServerDlg *pDlg = reinterpret_cast<CSocketTestServerDlg*>(p);
pDlg->ProcessClientRequest();
}
void CSocketTestServerDlg::ProcessClientRequest()
{
SOCKADDR_IN clientaddr;
struct hostent *hostentry;
int len = sizeof(clientaddr);
SOCKET clientsocket = accept(m_serversocket, (sockaddr*)&clientaddr, &len);
if(len == -1)
{
AfxMessageBox("Error accpeting the client socket");
}
else
{
char *p = inet_ntoa(clientaddr.sin_addr);
int portno = ntohs(clientaddr.sin_port);
// int inet_pton(int af, const char *restrict src, void *restrict dst);
char rbuf[1024];
recv(clientsocket, rbuf, 1024, 0);
for(int i = 1024; i >= 1; i--)
{
if(rbuf[i] == '\n' && rbuf[i - 1] == '\r')
{
rbuf[i-1] = '\0';
break;
}
}
CString strRecvData;
strRecvData.Format("%s\r\n%s %d\r\n%s\r\n\r\n", (const char*)CTime::GetCurrentTime().Format("%B %d, %Y %H:%M:%S"), p, portno, rbuf);
m_recvData += strRecvData;
m_bRefershData = true;
strcat(rbuf, "\r\n");
send(clientsocket, rbuf, 1024, 0);
closesocket(clientsocket);
}
}
void CSocketTestServerDlg::OnTimer(UINT_PTR nIDEvent)
{
int idx = nIDEvent;
if(m_bRefershData == true)
{
m_bRefershData = false;
UpdateData(FALSE);
}
fd_set fds;
struct timeval timeout;
int result;
timeout.tv_sec = 0;
timeout.tv_usec = 100;
FD_ZERO(&fds);
FD_SET(m_serversocket, &fds);
int rc = select(sizeof(fds)*8, &fds, NULL, NULL, &timeout);
if (rc==-1)
{
AfxMessageBox("ERROR selecting in the server socket");
return;
}
else if(rc > 0)
{
if (FD_ISSET(m_serversocket, &fds))
{
m_bRefershData = false;
HANDLE h = (HANDLE) ::_beginthread(f, 0, (void*) this);
}
}
CDialog::OnTimer(nIDEvent);
}
void CSocketTestServerDlg::OnBnClickedCancel()
{
OnCancel();
}
void CSocketTestServerDlg::OnBnClickedOk()
{
OnOK();
}