在VC中WININET如何使用HTTP的POST方法2007-08-21 13:30SUMMARY To properly simulate a Form submission using WinInet, you need to send a header that indicates the proper Content-Type. For Forms, the proper Content-Type header is: Content-Type: application/x-www-form-urlencoded
MORE INFORMATION In many cases, the server does not respond appropriately if a Content-Type is not specified. For example, the Active Server Pages component of IIS 3.0 actually checks this header specifically for 'application/x-www-form- urlencoded' before adding form variables to the "Request.Form" object. This MIME/Content-Type indicates that the data of the request is a list of URL- encoded form variables. URL-encoding means that space character (ASCII 32) is encoded as '+', special character such '!' encoded in hexadecemal form as '%21'.
Here is a snippet of code that uses the MFC WinInet classes to simulate a Form POST request: CString strHeaders = _T("Content-Type: application/x-www-form-urlencoded"); // URL-encoded form variables - // name = "John Doe", userid = "hithere", other = "P&Q" CString strFormData = _T("name=John+Doe&userid=hithere&other=P%26Q");
CInternetSession session("");
CHttpConnection* pServer = NULL; pServer = session.GetHttpConnection("www.xxxx.com",80);
pServer->OpenRequest(CHttpConnection::HTTP_VERB_POST,"/login.php");
//函数 PostData
//主要功能: Post方式向服务器传数据
//参数列表:
// 1、strUrl:提交地址
// 2、strPara:提交的参数
// 3、strContent:返回的网页内容
//返回值: 如果成功则返回true
//备注:
//****************************************************************************************//
bool PostData(CString strUrl, const CString &strPara, CString &strContent)
{
bool bRet = false;
CString strServer, strObject, strHeader, strRet;
unsigned short nPort;
DWORD dwServiceType;
if(!AfxParseURL(strUrl, dwServiceType, strServer, strObject, nPort))//不是有效有网络地址!
return false; CInternetSession sess;//Create session
CHttpFile* pFile = NULL;
CHttpConnection *pServer = sess.GetHttpConnection(strServer, nPort);
if(pServer == NULL)//连接服务器失败!
return false; pFile = pServer->OpenRequest(CHttpConnection::HTTP_VERB_POST,strObject,NULL,1,NULL,NULL,INTERNET_FLAG_EXISTING_CONNECT);
if(pFile == NULL)//找不到网络地址
return false; pFile -> AddRequestHeaders("Content-Type: application/x-www-form-urlencoded");
pFile -> AddRequestHeaders("Accept: */*");
pFile -> SendRequest(NULL,0,(LPTSTR)(LPCTSTR)strPara, strPara.GetLength()); CString strSentence;
DWORD dwStatus;
DWORD dwBuffLen = sizeof(dwStatus);
BOOL bSuccess = pFile->QueryInfo(
HTTP_QUERY_STATUS_CODE|HTTP_QUERY_FLAG_NUMBER,
&dwStatus, &dwBuffLen); if( bSuccess && dwStatus>= 200 && dwStatus<300)
{
char buffer[2049];
memset(buffer, 0, 2049);
int nReadCount = 0;
while((nReadCount = pFile->Read(buffer, 2048)) > 0)
{
strContent += buffer;
memset(buffer, 0, 2049);
}
bRet = true;
}
else//错误
bRet = false;
pFile->Close();
sess.Close();
return bRet;
}
To properly simulate a Form submission using WinInet, you need to send a header that indicates the proper Content-Type. For Forms, the proper Content-Type header is: Content-Type: application/x-www-form-urlencoded
MORE INFORMATION
In many cases, the server does not respond appropriately if a Content-Type is not specified. For example, the Active Server Pages component of IIS 3.0 actually checks this header specifically for 'application/x-www-form- urlencoded' before adding form variables to the "Request.Form" object. This MIME/Content-Type indicates that the data of the request is a list of URL- encoded form variables. URL-encoding means that space character (ASCII 32) is encoded as '+', special character such '!' encoded in hexadecemal form as '%21'.
Here is a snippet of code that uses the MFC WinInet classes to simulate a Form POST request:
CString strHeaders =
_T("Content-Type: application/x-www-form-urlencoded");
// URL-encoded form variables -
// name = "John Doe", userid = "hithere", other = "P&Q"
CString strFormData = _T("name=John+Doe&userid=hithere&other=P%26Q");
CInternetSession session;
CHttpConnection* pConnection =
session.GetHttpConnection(_T("ServerNameHere"));
CHttpFile* pFile =
pConnection->OpenRequest(CHttpConnection::HTTP_VERB_POST,
_T("FormActionHere"));
BOOL result = pFile->SendRequest(strHeaders,
(LPVOID)(LPCTSTR)strFormData, strFormData.GetLength());
Without MFC, the same code translates to straight SDK calls as follows:
static TCHAR hdrs[] =
_T("Content-Type: application/x-www-form-urlencoded");
static TCHAR frmdata[] =
_T("name=John+Doe&userid=hithere&other=P%26Q");
statuc TCHAR accept[] =
_T("Accept: */*");
// for clarity, error-checking has been removed
HINTERNET hSession = InternetOpen("MyAgent",
INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
HINTERNET hConnect = InternetConnect(hSession, _T("ServerNameHere"),
INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
HINTERNET hRequest = HttpOpenRequest(hConnect, "POST",
_T("FormActionHere"), NULL, NULL, accept, 0, 1);
HttpSendRequest(hRequest, hdrs, strlen(hdrs), frmdata, strlen(frmdata));