关于Http协议的get方法和post方法的区别和用法

(一)get方法和post方法简介

   查看了MSDN，并且实际写了一番程序，才明白get方法和post方法的不同。其实二者实现的功能相同，都是客户端提交数据库给服务器端，只是实现的机制不同而已。get方法实际上就是通过网页的URL地址实现数据的传送，而服务器端实现从URL地址中解析数据；而post方法则是通过表单的方式提交，数据采取加密方式传送，服务器接到请求后解析数据。从安全角度上看，post方法更安全，get方法可以直接从浏览器直接提交数据，而post方法则必须从网页提交表单。

(二)get方法和post方法实现

   啰嗦了一通，还是讲讲两种方法如何实现的吧。

1、get方法VC实现

   闲话少说，直接看代码，VC6.0标准类库函数CInternetSession,更详细的用法，请查看MSDN。

 

 CInternetSession  tInternet;
 CStdioFile*       tFile;
 char     tChars[2056];
 
 memset(tChars,0,2056);
 sprintf(tChars,"%s","http://127.0.0.1:8080/app?username=123&password=123&data=111111111111");

 tFile = tInternet.OpenURL(tChars,1, INTERNET_FLAG_TRANSFER_ASCII,NULL,0); 
 memset(tChars,0,2056);
 tFile->Read(tChars,2056);

 

    发送的超链接中，app是数据应用程序部署，在数据库端要有该程序的响应，数据库才会接收数据。程序的数据已经保存在了该URL中。

   其实发送URL的方法有很多，API函数，C++ Builder中的空间都可以实现该功能。

2、post方法实现

    (1)、仍然使用CInternetSession类     

     char chHeader[128];
     char chData[128];
     char tChars[128];
 
     memset(tChars,0,128);

     CInternetSession session;
     CHttpConnection* pConnection=NULL;
     CHttpFile* pFile=NULL;
     INTERNET_PORT nPort=8080;

 

     strcpy(chHeader,"Content-Type: application/x-www-form-urlencoded");
     strcpy(chData,"username=123&password=123&data=123456789012345");
 
     pConnection = session.GetHttpConnection("127.0.0.1",nPort);
     pFile = pConnection->OpenRequest(CHttpConnection::HTTP_VERB_POST,"/app");
     pFile->SendRequest(chHeader,(DWORD)strlen(chHeader),(LPVOID *)chData,strlen(chData));
     pFile->Read(tChars,128);
     session.Close();

(2)、使用TCP/IP协议传输数据

     SOCKADDR_IN   saServer;  
     LPHOSTENT     lphostent;  
     WSADATA       wsadata;  
     SOCKET        hsocket; 
     int           nRet;  
     const         char*   host_name="127.0.0.1";  
     char*        req=

                 "POST http://127.0.0.1:8080/app?username=123&password=123&data=111111111111   HTTP/1.1rn"  
                 "From:   localrn"  
                 "User-Agent:   receiver/Receiver/1.1rn"  
                 "Content-Type:   application/x-www-form-urlencodedrn"  
                 "Content-Length:   0rnrn";  
 
     char         tChars[128];

     if(WSAStartup(winsock_version,&wsadata))  
     {
          MessageBox("can't   initial   socket");
     }
 
     lphostent=gethostbyname(host_name);  
     if(lphostent==NULL)  
     {
          MessageBox("lphostent   is   null");
     }
 
     hsocket   =   socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);  
     saServer.sin_family   =   AF_INET;  
     saServer.sin_port   =   htons(8080);  
     saServer.sin_addr   =   *((LPIN_ADDR)*lphostent->h_addr_list);  
 
     nRet = connect(hsocket, (LPSOCKADDR)&saServer, sizeof(SOCKADDR_IN));  
     if(nRet == SOCKET_ERROR)  
     {   
          MessageBox("Can't connect"); 
          closesocket(hsocket);  
          return;  
     }  
     else   
     {
           MessageBox("connected   with host");
     }

     nRet = send(hsocket, req, strlen(req), 0);  
     if(nRet == SOCKET_ERROR)  
     {  
          MessageBox("send()   failed");
          closesocket(hsocket);  
     }  
     else  
     {
          MessageBox("send()   OK");
     }
 
     char   dest[1000];  
     nRet=0;  
     while(nRet>0)  
    {  
          nRet=recv(hsocket,(LPSTR)dest,sizeof(dest),0);  
          if(nRet>0)  

          { 
              dest[nRet]=0;

          }   
          else  
          {

              dest[0]=0;

          }  

          sprintf(tChars,"Received   bytes:%d",nRet);
          MessageBox(tChars);
          sprintf(tChars,"Result:%s",dest);  
          MessageBox(tChars);
     }  

(2)、使用API函数

      HINTERNET hInternetOpen = InternetOpen("http://127.0.0.1:8080/app",
           INTERNET_OPEN_TYPE_PRECONFIG,
           NULL,
           NULL,
           0);
      if(hInternetOpen < 0 )
      {
         MessageBox("Can't open the page");
      }

      HINTERNET hInternetConnect = InternetConnect(hInternetOpen,
           "127.0.0.1",
            8080,
            NULL,
           "HTTP/1.1",
            INTERNET_SERVICE_HTTP,
            0,
            0);
      if(hInternetConnect < 0 )
      {
         MessageBox("Can't connect to the server");
      }

      HINTERNET  hHttpOpenRequest = HttpOpenRequest(hInternetConnect,
            "POST",
            "/IFCS/IMEICheck",
            "HTTP/1.1",
             NULL,
             0,
             INTERNET_FLAG_RELOAD,
             0);
      if(hHttpOpenRequest < 0 )
      {
          MessageBox("Open request fail");
       } 

   
      char  chData[128] = "username=123&password=123&data=123456789000001";
      DWORD len = strlen(chData);

      int bRet = HttpSendRequest(hHttpOpenRequest,
            "Content-Type:   application/x-www-form-urlencodedrn",
             strlen("Content-Type:   application/x-www-form-urlencodedrn"),
            (LPVOID *)chData,
            len);

      char tChars[128];
      memset(tChars,0,128);
      DWORD dwReadLen;

      InternetReadFile(hHttpOpenRequest,(LPVOID *)tChars,128,&dwReadLen);
      if(dwReadLen > 0)
      {
          MessageBox(tChars);
       }
      else
      {
         MessageBox("Read the reply fail");
       }

      InternetCloseHandle(hHttpOpenRequest);
      InternetCloseHandle(hInternetConnect);
      InternetCloseHandle(hInternetOpen);