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WinInet MFC Classes



     Here is MFC classes' hierarchy. In MFC hierarchy you see

     CFtpConnection, CHttpConnection, and CGopherConnection classes are
     derived from CInternetConnection.
     
     
     
     CInternetSession
     
     CInternetSession is the first class to start an Internet session.
     This class warps InternetOpen API. Constructor of this class calls
     InternetOpen WinInet API, which opens an Internet connection.
     Other important function of this class is OpenUrl. This function
     actually calls InternetOpenUrl to open a URL. Here is the example:
     
     CInternetSession session;
     CStdioFile* file = session.OpenURL(
     "http://www.dotnetheaven.com");
     
     You can establish a connection with HTTP, FTP, or Gopher servers
     by calling its GetHttpConnection,
     GetFtpConnection or GetGopherConnection functions respectively.
     You can manage cookies by using three
     functions SetCookie, GetCookie, and GetCookieLength.
     
     Lets take a quick look on other CInternetSession functions. You
     can see MSDN for more details.
     
     Function

Description
     QueryOpen

Provides possible five asserts for error checking.
     SetOption

This member function is used to set options for
     the Internet session. See InternetQueryOption's dwOption parameter
     for more details.
     OpenURL

This function is a wrapper for InternetOpenURL
     API, which allows only downloading and reading the data from a
     URL.
     GetFtpConnection

Call this member function to establish an
     FTP connection and get a pointer to a CFtpConnection object.
     GetHttpConnection

Opens an HTTP server for an application
     that is trying to open a connection. You calll this member
     function to establish an HTTP connection and get a pointer to a
     CHttpConnection object.
     GetGopherConnection

Call this member function to establish a
     new gopher connection and get a pointer to a CGopherConnection
     object.
     EnableStatusCallback

Establishes a status callback routine.
     EnableStatusCallback is required for asynchronous operations.
     ServiceTypeFromHandle

Gets the type of service from the Internet
     handle.
     GetContext

Gets the context value for an Internet or
     application session.
     Close

Closes the Internet connection when the Internet session
     is terminated.
     SetCookie

Sets a cookie for the specified URL.
     GetCookie

Returns cookies for the specified URL and all its
     parent URLs.
     GetCookieLength

Retrieves the variable specifying the length of
     the cookie stored in the buffer.
     OnStatusCallback

Updates the status of an operation when
     status callback is enabled.
     CInternetFile
     
     As you can see in the hierarchy chart, CInternetFile class is
     derived from CStdioFile. CInternetFile is base class
     for CHttpFile and CGopherFile, which allows you to access remote,
     files on HTTP and Gopher servers. Here are
     its members.
     
     Members

Description
     SetWriteBufferSize

Sets the size of the buffer where data
     will be written.
     SetReadBufferSize

Sets the size of the buffer where data
     will be read.
     Seek

Repositions the pointer in an open file.
     Read

Read the # of specified bytes.
     Write

Write the number of specified bytes.
     Abort

Closes the file, ignoring all warnings and errors.
     Flush

Flushes the contents of the write buffer and makes sure
     the data in memory is written to the target machine.
     Close

Closes a CInternetFile and frees its resources
     ReadString

Reads a stream of characters.
     m_hFile

A handle to a file.
     Here is how to use this class:
     
     HINTERNET hRequest = HttpOpenRequest( hConnection, "GET", "",
     NULL, NULL, INTERNET_FLAG_RELOAD, 0  );
     
     NOTE: You must call delete to free this file from memory.
     
     CInternetConnection
     
     This class is a base class for CHttpConnection, CFtpConnection,
     and CGopherConnection classes. You always
     create this class using methods of CInternetSession. Since you
     create this class dynamically using
     CInternetSession, you must always call delete to free it from
     memory. You probably don't have to use in your
     program. Its has only three member functions.
     
     
     Members

Description
     GetContext

Gets the context ID for this connection object.
     GetSession

Gets a pointer to the CInternetSession object
     associated with the connection.
     GetServerName

Gets the name of the server associated with the
     connection.
     WinInet HTTP MFC Classes
     
     CHttpConnection
     
     This class manages connection to an HTTP server. You create this
     class object dynamically by calling
     CInternetSession::GetHttpConnection. You never create
     CHttpConnection directly. This class has only one
     member fdunction:
     
     Members

Description
     OpenRequest

Opens an HTTP request.
     This function returns a pointer to CHttpFile. Here are syntaxes of
     this function:
     
     CHttpFile* OpenRequest( LPCTSTR pstrVerb, LPCTSTR pstrObjectName,
     LPCTSTR pstrReferer = NULL, DWORD
     dwContext = 1, LPCTSTR* pstrAcceptTypes = NULL, LPCTSTR
     pstrVersion = NULL, DWORD dwFlags =
     INTERNET_FLAG_EXISTING_CONNECT );
     
     CHttpFile* OpenRequest( int nVerb, LPCTSTR pstrObjectName, LPCTSTR
     pstrReferer = NULL, DWORD dwContext
     = 1, LPCTSTR* pstrAcceptTypes = NULL, LPCTSTR pstrVersion = NULL,
     DWORD dwFlags =
     INTERNET_FLAG_EXISTING_CONNECT );
     
     Here I am interested in nVerb parameter only. See MSDN for more
     details.
     
     nVerb This parameter tells the request type to the server number
     It Can be one of the following:
     
     
     HTTP request type

nVerb value
     HTTP_VERB_POST

0
     HTTP_VERB_GET

1
     HTTP_VERB_HEAD

2
     HTTP_VERB_PUT

3
     HTTP_VERB_LINK

4
     HTTP_VERB_DELETE

5
     HTTP_VERB_UNLINK

6
     Here is how to use this class:
     
     HINTERNET hRequest = HttpOpenRequest( hConnection, "GET", "",
     NULL, NULL, INTERNET_FLAG_RELOAD, 0  );
     
     CHttpFile
     
     This class encapsulates rest of the HTTP APIs. All methods are
     easy to understand.
     
     Members

Description
     AddRequestHeaders

Adds headers to the request sent to an
     HTTP server.
     SendRequest

Sends a request to an HTTP server.
     SendRequestEx

Sends a request to an HTTP server using the Write
     or WriteString methods of CInternetFile.
     EndRequest

Ends a request sent to an HTTP server with the
     SendRequestEx member function.
     QueryInfo

Returns the response or request headers from the
     HTTP server.
     QueryInforStatusCode

Retrieves the status code associated with
     an HTTP request and places it in the supplied dwStatusCode
     parameter.
     GetVerb

Gets the verb that was used in a request to an HTTP
     server.
     GetObject

Gets the target object of the verb in a request to
     an HTTP server.
     GetFileURL

Gets the URL for the specified file.
     Close

Closes the CHttpFile and frees its resources.
     WinInet FTP MFC Classes
     
     FTP Classes
     
     CFtpConnection and CFtpFindFile are two FTP classes, which
     encapsulate all MFC APIs.
     
     CFtpConnection
     
     This class manages connection to your FTP server and allows direct
     manipulation of files and directories on the
     server. You always create a CFtpConnection object using
     CInternetSession::GetFtpConnection. All member of
     this class are easy to understand. We will see how to use these
     functions in our sample example.
     
     
     Members

Description
     SetCurrentDirectory

Sets the current FTP directory.
     GetCurrentDirectory

Gets the current FTP directory.
     GetCurrentDirectoryAsURL

Get current dir as a URL.
     RemoveDirectory

Removes the specified dir.
     CreateDirectory

Creates a new dir.
     Rename

Rename a file or a dir.
     Remove

Removes a file.
     PutFile

Uploads a file to the server.
     GetFile

Download a file from the server.
     OpenFile

Opens a file and returns a pointer to
     CInternetFile.
     Close

Closes the connection.
     CFtpFindFile
     
     CFindFileFile is used to find a file on the server.
     
     Members

Description
     FindFile

Finds a file on the server. It returns nonzero if
     successful, otherwise 0.
     FindNextFile

Use to continue to search for a file, which you
     started with FindFile.
     GetFileURL

Gets the URL for a specified file.
     Some code snippets:
     
     CFtpConnection* m_pFtpConnection;
     m_pFtpConnection = m_pInetSession->GetFtpConnection(strServerName,
     szftpUserID, szftpPassword, nPort,
     FALSE);
     // Do connection to the FTP server
     if ( m_pFtpConnection->PutFile(lpExePath + "default.asp",
     "default.asp", FTP_TRANSFER_TYPE_BINARY, 1) ==
     1 )
     AddLog("File : default.asp uploaded successfully.");
     else
     AddLog("Error in file :default.asp upload.");
     
     FTP Example: MSDN has an excellent example of FTP. There is
     nothing left after that example.
     
     WinInet Gopher MFC Classes
     
     Gopher Classes
     
     CGopherConnection, CGopherFile, CGopherFindFile, and
     CGopherLocator are four gopher classes. I don't see any
     practical use of Gopher here. So why don't I save some of my time
     of next tutorial. May be some of you guys
     will complete this part :). Let's party tonite.
     
     Other Classes
     
     CInternetExeption
     
     This class is for internet exception handling. It is derived from
     CException. You will see use of this class in my
     examples.
     
     Other chapters of this tutorial
     
     Introduction to WinInet.
     Working with Common WinInet APIs.
     WinInet APIs for HTTP and FTP with sample examples.

     Advanced WinInet and Security Issues.

http://www.dotnetheaven.com/uploadfi...85341am/wininetmfcclasses.aspx


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※ 來源: DISP BBS (http://disp.twbbs.org)
※ 作者: ott  來自: 118.166.4.170  時間: 2010-01-13 16:08:22