FILE: Specifying FileVersion and #Version for Component Download

• Microsoft Internet Explorer (Programming), versions 3.0, 3.01, 3.02, 4.0

SUMMARY

Update of components over the Web is usually controlled by the component's file version. This file version can be specified either by the #Version in the CODEBASE attribute of the <OBJECT> tag or the FileVersion keyword in the .inf file. Determining the file version can be confusing, and if not specified correctly, could cause the component to download incorrectly.

MORE INFORMATION

For the <OBJECT> tag, specify the file version using the CODEBASE attribute in this manner:

   <OBJECT ID="BoomButton" WIDTH=225 HEIGHT=35
    CLASSID="CLSID:56F1BF40-B2D0-11d0-A6D6-00AA00A70FC2"
    CODEBASE="http://example.microsoft.com/AControl.cab#Version=1,0,0,1">
   ...

   Check the Registry for CLSID
   If CLSID of OBJECT is NOT found in the registry
      Download OBJECT
   Else If no #Version specified in CODEBASE tag
      Use OBJECT installed on system
   Else
      Check InprocServer32 key for location of installed component
      If File version of installed component < CODEBASE #Version Tag
         Download OBJECT

Update of components installed via an .inf file is controlled by the FileVersion keyword in the .inf file. For example, the following syntax controls the installation of mfc42.dll for the VC 4.2b control above:

   [mfc42.dll]
   FileVersion=4,2,0,6256
   hook=mfc42installer

   Search for mfc42.dll in the system (first looking at the same directory
   as the previous version of the control being installed; if not found,
   the file is searched for via the standard search path for DLLs)
   If mfc42.dll is not found,
      install mfc42.dll
   Else
    Compare the file version of the DLL with the FileVersion keyword
    specified in the .inf file

   Mfc42.dll:     reported - 4.21.7022  use - 4,21,0,7022
   Msvcrt.dll:    reported - 5.00.7022  use - 5,0,0,7022
   Olepro32.dll:  reported - 5.0.4055   use - 5,0,4055,1

1. From the Developer Studio File menu, select Open, click Open as, and click Resources.

2. Open the version resource and you will find a FILEVERSION key. This is the proper version to use in the <OBJECT> tag or in the .inf file.

3. Notice that there is another "FileVersion" key following the Block Header portion of the version resource. This is the version displayed by the Windows shell, and may be different in some cases from the FILEVERSION value in #2 above.

   GetVers <filename>

 ~ Getvers.exe (size: 40960 bytes) 

   ARTICLE-ID: Q119591
   TITLE     : How to Obtain Microsoft Support Files from Online Services

   void reportError()
   {
       LPVOID lpMsgBuf;

       FormatMessage(
           FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
           NULL,
           GetLastError(),
           MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
           (LPTSTR) &lpMsgBuf,
           0,
           NULL );

       cout << (char*)lpMsgBuf << "\n";

       // Free the buffer.
       LocalFree( lpMsgBuf );
   }

   void main( int argc, char *argv[ ], char *envp[ ] )
   {
       cout << "\n";

       if(2 != argc)
       {
           cout << "Syntax: GetVer <File Name>\n";
           return;
       }

       DWORD dwArg;
       DWORD dwInfoSize = GetFileVersionInfoSize(argv[1], &dwArg;);

       if(0 == dwInfoSize)
       {
           cout << "No version info available\n";
           reportError();
           return;
       }

       BYTE* lpBuff = new BYTE[dwInfoSize];

       if(!lpBuff)
       {
           cout << "Out of Memory\n";
           return;
       }

       if(0 == GetFileVersionInfo(argv[1], 0, dwInfoSize, lpBuff))
       {
           cout << "Error retrieving version info\n";
           reportError();
           return;
       }

       VS_FIXEDFILEINFO *vInfo;

       UINT uInfoSize;

       if(0 == VerQueryValue(lpBuff, TEXT("\\"),
               (LPVOID*)&vInfo,
               &uInfoSize))
       {
           cout << "Version information not available\n";
           delete lpBuff;
           return;
       }

       if(0 == uInfoSize)
       {
           cout << "Version information not available\n";
           delete lpBuff;
           return;
       }

       cout << argv[1]
           << " Version: "
           << HIWORD(vInfo->dwFileVersionMS) << ","
           << LOWORD(vInfo->dwFileVersionMS) << ","
           << HIWORD(vInfo->dwFileVersionLS) << ","
           << LOWORD(vInfo->dwFileVersionLS) << "\n";

       delete lpBuff;
   }

Keywords          : AXSDKCompDownload
Version           : 3.0 3.01 3.02 4.0
Platform          : WINDOWS