三種獲取網頁源碼的方法(使用MFC/Socket實現)

2020-01-26 15:39:30

字體：大中小

來源：轉載

供稿：網友

第一個方法是使用MFC里面的

<afxinet.h>

CString GetHttpFileData(CString strUrl)
{
     CInternetSession Session("Internet Explorer", 0);
     CHttpFile *pHttpFile = NULL;
     CString strData;
     CString strClip;
     pHttpFile = (CHttpFile*)Session.OpenURL(strUrl);
    while ( pHttpFile->ReadString(strClip) )
     {
      strData += strClip;
      }
     return strData;
}

要講一下，pHttpFile->ReadString() 每次可能只讀一個數據片斷，讀多少次取決于網絡狀況，所以要把每次讀到的數據加到總數據的尾部，用了CString 省去了緩沖區處理:)
別忘了包含頭文件#include <afxinet.h> 在工程設置，里面要選擇 using MFC 要不然編譯不了

第二種是使用WinNet的純API實現的

復制代碼代碼如下:

#define MAXBLOCKSIZE 1024
#include <windows.h>
#include <wininet.h>

#pragma comment(lib, "wininet.lib")

void GetWebSrcCode(const char *Url);

int _tmain(int argc, _TCHAR* argv[])
{
GetWebSrcCode("http://www.49028c.com/");

return 0;
}

void GetWebSrcCode(const char *Url)
{
    HINTERNET hSession = InternetOpen("zwt", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
    if (hSession != NULL)
    {
        HINTERNET hURL = InternetOpenUrl(hSession, Url, NULL, 0, INTERNET_FLAG_DONT_CACHE, 0);
        if (hURL != NULL)
        {
            char Temp[MAXBLOCKSIZE] = {0};
            ULONG Number = 1;

            FILE *stream;
            if( (stream = fopen( "E://test.html", "wb" )) != NULL )
            {
                while (Number > 0)
                {
                    InternetReadFile(hURL, Temp, MAXBLOCKSIZE - 1, &Number);
                    fwrite(Temp, sizeof (char), Number , stream);
                }
                fclose( stream );
            }

            InternetCloseHandle(hURL);
            hURL = NULL;
        }

        InternetCloseHandle(hSession);
        hSession = NULL;
    }
}

第三種就是使用非封裝過的Socket實現了

復制代碼代碼如下:

int main(int argc, char* argv[])
{
    SOCKET hsocket;
    SOCKADDR_IN saServer;
    WSADATA wsadata;
    LPHOSTENT lphostent;
    int nRet;
    char Dest[3000];
    char* host_name="blog.sina.com.cn";
    char* req="GET /s/blog_44acab2f01016gz3.html HTTP/1.1/r/n"
        "User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET4.0C; .NET4.0E; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)/r/n"
        "Host:blog.sina.com.cn/r/n/r/n";

    // 初始化套接字
    if(WSAStartup(MAKEWORD(2,2),&wsadata))
        printf("初始化SOCKET出錯！");
    lphostent=gethostbyname(host_name);
    if(lphostent==NULL)
        printf("lphostent為空！");
    hsocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
    saServer.sin_family = AF_INET;
    saServer.sin_port = htons(80);
    saServer.sin_addr =*((LPIN_ADDR)*lphostent->h_addr_list);
    // 利用SOCKET連接
    nRet = connect(hsocket,(LPSOCKADDR)&saServer,sizeof(SOCKADDR_IN));
    if(nRet == SOCKET_ERROR)
    {
        printf("建立連接時出錯！");
        closesocket(hsocket);
        return 0;
    }
    // 利用SOCKET發送

    nRet = send(hsocket,req,strlen(req),0);
    if(nRet==SOCKET_ERROR)
    {
        printf("發送數據包時出錯！");
        closesocket(hsocket);
    }
    nRet=1;
    while(nRet>0)
    {
        // 接收返回數據包
        nRet=recv(hsocket,(LPSTR)Dest,sizeof(Dest),0);
        if(nRet>0)
            Dest[nRet]=0;
        else
            Dest[0]=0;
        char sDest[3000] = {0};
        UTF8_2_GB2312(sDest,nRet,Dest,nRet);
        // 顯示返回數據包的大小、內容
        //printf("/nReceived bytes:%d/n",nRet);
        printf("Result:/n%s",sDest);
    }
}

另外，以上我們獲取網頁的時候，獲取到的可能是UTF8，似乎目前大多數網站都用的這種編碼吧！下面是編碼轉換。

復制代碼代碼如下:

void UTF_8ToUnicode(wchar_t* pOut,char *pText)
{   
    char* uchar = (char *)pOut; 
    uchar[1] = ((pText[0] & 0x0F) << 4) + ((pText[1] >> 2) & 0x0F);
    uchar[0] = ((pText[1] & 0x03) << 6) + (pText[2] & 0x3F); 
} 
void Gb2312ToUnicode(wchar_t* pOut,char *gbBuffer) 
{   
    ::MultiByteToWideChar(CP_ACP,MB_PRECOMPOSED,gbBuffer,2,pOut,1);
} 
void UTF_8ToGB2312(char*pOut, char *pText, int pLen)  
{   
    char Ctemp[4];   
    memset(Ctemp,0,4); 
    int i =0 ,j = 0; 
    while(i < pLen) 
    {  
        if(pText[i] >= 0)  
        {  
            pOut[j++] = pText[i++]; 
        } 
        else 
        {  
            WCHAR Wtemp; 
            UTF_8ToUnicode(&Wtemp,pText + i);
            UnicodeToGB2312(Ctemp,Wtemp); 
            pOut[j] = Ctemp[0];
            pOut[j + 1] = Ctemp[1];  
            i += 3;   
            j += 2;  
        }   
    } 
    pOut[j] ='/n'; 
    return; 
}