在VC中WININET如何使用HTTP的POSTA和GET方法

在VC中WININET如何使用HTTP的POSTA和GET方法　2009-02-13 16:35
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Post资料：

SUMMARY

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 '!'.

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&Q");

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&Q");

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));

// close any valid internet-handles

我这里有一段程序，用来在一个对话框里显示出一次http request的原始信息，不过使用Inet API做的，希望能有帮助。

void CHTTPRequestDlg::OnButtonRequest()

{

UpdateData(TRUE);

HINTERNET hInternet = InternetOpen("Mozilla/4.0 (compatible; MSIE 5.0; Windows NT 5.0)",

INTERNET_OPEN_TYPE_DIRECT,

NULL,

NULL,

NULL);

HINTERNET hSession = InternetConnect(hInternet,

m_strHost,

m_nPort,

"username",

"password",

INTERNET_SERVICE_HTTP,

0,

0);

char* szAccept[] = {"*/*",NULL};

CString strVerb;

m_comboVerb.GetWindowText(strVerb);

HINTERNET hRequest = HttpOpenRequest(hSession,

strVerb,

m_strObject,

NULL,

NULL,

(LPCSTR*)szAccept,

0,

0);

struct

{

char* Language;

char* Encoding;

char* ContentType;

}Headers = {"Accept-Language:zh-cn\r\n",

"Accept-Encoding:gzip,deflate\r\n",

"Content-Type:application/x-www-form-urlencoded\r\n"};



if(m_bLanguage)

{

HttpAddRequestHeaders(hRequest,

Headers.Language,

-1,

HTTP_ADDREQ_FLAG_ADD|HTTP_ADDREQ_FLAG_REPLACE);

}

if(m_bEncoding)

{

HttpAddRequestHeaders(hRequest,

Headers.Encoding,

-1,

HTTP_ADDREQ_FLAG_ADD|HTTP_ADDREQ_FLAG_REPLACE);

}

if(m_bContentType)

{

HttpAddRequestHeaders(hRequest,

Headers.ContentType,

-1,

HTTP_ADDREQ_FLAG_ADD|HTTP_ADDREQ_FLAG_REPLACE);

}

LPCSTR lpAddHeader = NULL;

LPCSTR lpContent = NULL;

if(m_strHeaders.GetLength())

{

if(m_strHeaders.Right(2) != "\r\n")

{

m_strHeaders+="\r\n";

}

lpAddHeader = (LPCSTR)m_strHeaders;

}

if(m_strContent.GetLength() && (strVerb == "POST" || strVerb == "PUT"))

{

lpContent = (LPCSTR)m_strContent;

}

HttpSendRequest(hRequest,

lpAddHeader,

-1,

(LPVOID)lpContent,

m_strContent.GetLength());



m_editContentGot.SetSel(0,-1);

m_editContentGot.ReplaceSel("");



LPSTR lpszData; //buffer for the data

DWORD dwSize; //size of the data available

DWORD dwDownloaded; //size of the downloaded data



//Set the cursor to an hourglass.

SetCursor(LoadCursor(NULL,IDC_WAIT));



// This loop handles reading the data.

while(1)

{

// The call to InternetQueryDataAvailable determines the amount of

// data available to download.

if (!InternetQueryDataAvailable(hRequest,&dwSize,0,0))

{

SetCursor(LoadCursor(NULL,IDC_ARROW));

break;

}

else

{

// Allocates a buffer of the size returned by InternetQueryDataAvailable

lpszData = new char[dwSize+1];



// Reads the data from the HINTERNET handle.

if(!InternetReadFile(hRequest,(LPVOID)lpszData,dwSize,&dwDownloaded))

{

delete[] lpszData;

break;

}

else

{

// Adds a null terminator to the end of the data buffer

lpszData[dwDownloaded]='\0';



int nLen = m_editContentGot.GetWindowTextLength();

m_editContentGot.SetSel(nLen-1, nLen-1);

m_editContentGot.ReplaceSel(lpszData);



// Delete the two buffers

delete[] lpszData;



// Check the size of the remaining data. If it is zero, break.

if (dwDownloaded == 0)

{

break;

}

}

}

}



// Close the HINTERNET handle

InternetCloseHandle(hRequest);

InternetCloseHandle(hSession);

InternetCloseHandle(hInternet);



// Set the cursor back to an arrow

SetCursor(LoadCursor(NULL,IDC_ARROW));

}

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关文件：#include

使用MFC示例如下:

首先设置m_strRequest请求字符串 eg."name=aaa&pass=bbb";

m_strServerName 服务器名称或者IP eg."www.yahoo.com"

m_strObjectName 请求文件位置 eg. "pub/aaa.asp"

请求的结果存放在m_strHtml中

void func()

{

CInternetSession m_InetSession("session");

CHttpConnection *pServer = NULL;

CHttpFile* pFile = NULL;

try

{

INTERNET_PORT nPort;

nPort=80;

pServer = m_InetSession.GetHttpConnection(m_strServerName, nPort);

pFile = pServer->OpenRequest(CHttpConnection::HTTP_VERB_POST,m_strObjectName);

char szHeaders[100];

strcpy(szHeaders,"Accept: text*/*\r\nContent-Type: application/x-www-form-urlencoded");

pFile->AddRequestHeaders(szHeaders);



pFile->SendRequestEx(m_strRequest.GetLength());

pFile->WriteString(m_strRequest);//重要-->m_Request 中有"name=aaa&name2=BBB&"

pFile->EndRequest();

DWORD dwRet;

pFile->QueryInfoStatusCode(dwRet);

CString str;



//m_Mutex.Lock();

m_strHtml="";

char szBuff[1024];

if (dwRet == HTTP_STATUS_OK)

{

UINT nRead;

while ((nRead = pFile->Read(szBuff,1023))>0)

{

m_strHtml += CString(szBuff,nRead);

}

}

//m_Mutex.Unlock();



delete pFile;

delete pServer;

}

catch (CInternetException* e)

{

CString s;

s.Format("Internet Exception\r\nm_dwError%u,m_dwContextError%u",e->m_dwError,e->m_dwContext);

AfxMessageBox(s);

//catch errors from WinInet

}

}

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1、获得WebBrowser Control的DWebBrowserEvents2::DocumentComplete事件

2、在DWebBrowserEvents2::DocumentComplete事件中根据IWebBrowser2::Document获得IHTMLDocument2

3、IHTMLDocument2::forms得到IHTMLElementCollection

4、在IHTMLElementCollection中根据name、tagName、ID得到指定的IHTMLElement

5、从IHTMLElement得到IHTMLFormElement

6、执行IHTMLFormElement::submit

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要正确模拟表单提交使用 WinInet, 您需要发送一个指示正确 Content-Type 标头。 对于窗体, 正确 Content-Type 标题是:

Content-Type: application/x-www-form-urlencoded

如果没有指定 Content-Type 在许多情况下, 服务器不响应正确。 在之前将表单变量添加到 " Request.Form "

对象例如, IIS 3.0 的 ActiveServerPages 组件实际上检查专门用于应用表单 ' www 程序 / x -

urlencoded ' 此标题。 此 MIME / 内容类型指示请求数据是 - URL 编码窗体变量的列表。 URL 编码意味着空格字符

(ASCII 32) 被编码为 + ' '， 特殊字符如 ' ! ' 以十六进制形式编码为 21 % '。

下面是使用 MFCWinInet 类来模拟 FormPOST 请求的代码段：

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());



没有 MFC, 相同的代码将转换为直 SDK 调用如下：

static TCHAR hdrs[] =

_T("Content-Type: application/x-www-form-urlencoded");

static TCHAR frmdata[] =

_T("name=John+Doe&userid=hithere&other=P%26Q");

static LPSTR accept[2]={"*/*", NULL};

// 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));

// close any valid internet-handles

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Get资料：

#include "winsock2.h"

#include "stdio.h"

#include "Wininet.h"

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

void main()

{

HINTERNET hNet = ::InternetOpen("Google page", //当HTTP协议使用时，这个参数随意赋值

PRE_CONFIG_INTERNET_ACCESS, //访问类型指示Win32网络函数使用登记信息去发现一个服务器。

NULL,

INTERNET_INVALID_PORT_NUMBER, //使用INTERNET_INVALID_PORT_NUMBER相当于提供却省的端口数。

0 //标志去指示使用返回句句柄的将来的Internet函数将"不"为回调函数发送状态信息

) ;

HINTERNET hUrlFile = ::InternetOpenUrl(hNet, //从InternetOpen返回的句柄

"http://www.google.com", //需要打开的URL

NULL, //用来向服务器传送额外的信息,一般为NULL

0, //用来向服务器传送额外的信息,一般为 0

INTERNET_FLAG_RELOAD, //InternetOpenUrl行为的标志

0) ; //信息将不会被送到状态回调函数

char buffer[1024] ;

DWORD dwBytesRead = 0;

BOOL bRead = ::InternetReadFile(hUrlFile, //InternetOpenUrl返回的句柄

buffer, //保留数据的缓冲区

sizeof(buffer),

&dwBytesRead); //指向包含读入缓冲区字节数的变量的指针;

//如果返回值是TRUE，而且这里指向0，则文件已经读到了文件的末尾。

::InternetCloseHandle(hUrlFile) ;

::InternetCloseHandle(hNet) ;

printf("%s", buffer);

}