Question

关于Http协议的get方法和post方法的区别和用法

Answer 1

(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/1.1\r\n"
"From: local\r\n"
"User-Agent: receiver/Receiver/1.1\r\n"
"Content-Type: application/x-www-form-urlencoded\r\n"
"Content-Length: 0\r\n\r\n";

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-urlencoded\r\n",
strlen("Content-Type: application/x-www-form-urlencoded\r\n"),
(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);