Knowledge Base Nr: 00244 WinCESocket.cpp - http://www.swe-kaiser.de

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MFC/WinCE: Sockethandling - Schreiben und Lesen HTTP-Request

  
////// beispiel
BOOL CHellosocketDlg::OnInitDialog()
{
    // Allow only one instance of the application.
    HWND hWnd = ::FindWindow (TEXT("hellosocket"), NULL);
    if (hWnd)
    {
        ::SetForegroundWindow ((HWND)(((DWORD)hWnd) | 0x01));
        return -1;
    }
...
    GetDlgItem(IDC_HOST)->SetWindowText(TEXT("krserver"));
    GetDlgItem(IDC_PORT)->SetWindowText(TEXT("80"));
    GetDlgItem(IDC_REQ)->SetWindowText(TEXT("HEAD /kaiserreich/"));
...
}

#include "../../msvc60/cpp_classes/WinCESupport.h"

void CHellosocketDlg::OnButton1()
{
    GetDlgItem(IDC_MSG)->SetWindowText(TEXT(""));

    CString strHost, strReq, strPort, strRecv;

    GetDlgItem(IDC_HOST)->GetWindowText(strHost);
    GetDlgItem(IDC_REQ)->GetWindowText(strReq);
    GetDlgItem(IDC_PORT)->GetWindowText(strPort);

    int nPortNo = _wtoi(strPort);

    HWND hWnd = 0;
    if (IsDlgButtonChecked(IDC_DEBUG))
        hWnd = GetSafeHwnd();

    int nErr = SendAndReceiveSocket(hWnd
                                  , strHost, strReq, nPortNo
                                  , strRecv);
    ASSERT(!nErr);

    GetDlgItem(IDC_MSG)->SetWindowText(strRecv);
}

////// implementierung

#include <afxwin.h>
#include <winsock.h>

#include "WinCESupport.h"

int SendAndReceiveSocket(HWND hWnd, LPCTSTR lpwszHost, LPCTSTR lpwszReq, int nPortNo, CString& strRecv)
{
////
    char szReq[200] = {0};
    char szHost[100] = {0};


    ::WideCharToMultiByte(CP_ACP, 0
        , lpwszHost, wcslen(lpwszHost)
        , szHost, sizeof(szHost)
        , NULL, NULL);
    ::WideCharToMultiByte(CP_ACP, 0
        , lpwszReq, wcslen(lpwszReq)
        , szReq, sizeof(szReq)
        , NULL, NULL);
////

    char szRequest[300] = {0};
    int index = 0;                      // Integer index
    int iReturn = 0;                    // Return value of recv function
    char szClientA[4000];                // ASCII string
    TCHAR szClientW[4000];               // Unicode string
    TCHAR szError[100];                 // Error message string

    SOCKET ServerSock = INVALID_SOCKET; // Socket bound to the server
    SOCKADDR_IN destination_sin;        // Server socket address
    PHOSTENT phostent = NULL;           // Points to the HOSTENT structure
    WSADATA WSAData;                    // Contains details of the

    sprintf(szRequest,
        "%s HTTP/1.1\n"
        "Host: %s\n"
        "Connection: close\n"
        "\n",
        szReq, szHost);

    // Initialize Winsocket.
    if (WSAStartup (MAKEWORD(1,1), &WSAData) != 0)
    {
        wsprintf (szError, TEXT("WSAStartup failed. Error: %d"),
            WSAGetLastError ());
        if (hWnd)
            ::MessageBox (hWnd, szError, TEXT("Error"), MB_OK);
        return -1;
    }

    // Create a TCP/IP socket that is bound to the server.
    if ((ServerSock = socket (AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET)
    {
        wsprintf (szError, TEXT("Allocating socket failed. Error: %d"),
            WSAGetLastError ());
        if (hWnd)
            ::MessageBox (hWnd, szError, TEXT("Error"), MB_OK);
        return -2;
    }

    // Fill out the server socket's address information.
    destination_sin.sin_family = AF_INET;
    phostent = gethostbyname (szHost);

    if (phostent == NULL)
    {
        wsprintf (szError, TEXT("Unable to get the host name. Error: %d"),
            WSAGetLastError ());
        if (hWnd)
            ::MessageBox (hWnd, szError, TEXT("Error"), MB_OK);
        strRecv += szError;

        closesocket (ServerSock);
        return -3;
    }

    // Assign the socket IP address.
    memcpy ((char FAR *)&(destination_sin.sin_addr),
            phostent->h_addr,
            phostent->h_length);

    // Convert to network ordering.
    destination_sin.sin_port = htons (nPortNo);

    // Establish a connection to the server socket.
    if (connect (ServerSock,
        (PSOCKADDR) &destination_sin,
        sizeof (destination_sin)) == SOCKET_ERROR)
    {
        wsprintf (szError,
            TEXT("Connecting to the server failed. Error: %d"),
            WSAGetLastError ());
        if (hWnd)
            ::MessageBox (hWnd, szError, TEXT("Error"), MB_OK);
        closesocket (ServerSock);
        strRecv += szError;
        return -4;
    }

    // Send request to the server.
    if (send (ServerSock, szRequest, strlen (szRequest) + 1, 0)
        == SOCKET_ERROR)
    {
        wsprintf (szError,
            TEXT("Sending data to the server failed. Error: %d"),
            WSAGetLastError ());
        strRecv += szError;
        if (hWnd)
            ::MessageBox (hWnd, szError, TEXT("Error"), MB_OK);
    }

    // Disable sending on ServerSock.
    shutdown (ServerSock, 0x01);

    strRecv = "";

    for (;;)
    {
        // Receive data from the server socket.
        memset(szClientA, sizeof(szClientA), 0);
        iReturn = recv (ServerSock, szClientA, sizeof(szClientA), 0);

        // Check if there is any data received. If there is, display it.
        if (iReturn == SOCKET_ERROR)
        {
            wsprintf (szError, TEXT("No data is received, recv failed.")
                TEXT(" Error: %d"), WSAGetLastError ());
            if (hWnd)
                ::MessageBox (hWnd, szError, TEXT("Client"), MB_OK);
            strRecv += szError;
            break;
        }
        else if (iReturn == 0)
        {
            //Finished receiving data
            break;
        }
        else
        {
            //todo: Convert the ASCII string to a Unicode string.
            memset(szClientW, sizeof(szClientW), 0);
            for (index = 0; index <= sizeof(szClientA); index++)
                szClientW[index] = szClientA[index];
            szClientW[iReturn] = 0;

            strRecv += szClientW;
        }
    }

    // Disable receiving on ServerSock.
    shutdown (ServerSock, 0x00);

    // Close the socket.
    closesocket (ServerSock);

    WSACleanup ();

    return 0;
}