IJournalReader::ReadFromStream method

Artikel
06/01/2022

Takes a stream to a Journal Note file and returns an XML stream representing the contents of the document.

Note

The Journal Reader component cannot read Windows Journal files created by machines running Windows 7 or later. The IJournalReader interface should be considered deprecated or obsolete and should not be used.

Syntax

HRESULT ReadFromStream(
  [in]          IStream *pJournalFileStream,
  [out, retval] IStream **ppXmlStream
);

Parameters

pJournalFileStream [in]: An IStream object representing the Journal file to read.
ppXmlStream [out, retval]: A pointer to the address of an IStream object that will receive the XML stream created by reading the Journal file.

Return value

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

Streams are used to avoid direct access to the file system and to allow choice in which XML parsing method to use.

Examples

The following example of a handler for a button's Click event creates an instance of the IJournalReader Interface interface and uses it to read an existing Journal file.

void CJntlReaderMFCDlg::OnBnClickedButton1()
{
  IStream* pJntStream;
  IStream* pXmlStream;
  IJournalReader* pJntReader;
  HRESULT hr;
  CString szFileName = "";
  static char BASED_CODE szFilter[] = 
    "Journal files (*.jnt)|*.jnt|All files (*.*)|*.*";
  CFileDialog* fileDialog = new CFileDialog(TRUE, "*.jnt", NULL, 
                                 OFN_FILEMUSTEXIST, szFilter, this);

  // Get the filename from the user by using a File Open dialog
  if (IDOK == fileDialog->DoModal())
  {
    szFileName = fileDialog->GetPathName();

    // Read a JNT file into a memory buffer
    HANDLE hFile = CreateFile(szFileName.GetBuffer(), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
    
    if (INVALID_HANDLE_VALUE != hFile)
    {
      // Allocate memory to hold the file contents
      DWORD dwFileSize = GetFileSize(hFile, NULL);
      HGLOBAL hGlobal = GlobalAlloc(GHND, dwFileSize);

      if (hGlobal != NULL)
      {
        LPBYTE pData = (LPBYTE)GlobalLock(hGlobal);

        if (pData != NULL)
        {
          DWORD dwRead;

          // Read the Journal file into the pData buffer
          if (ReadFile(hFile, pData, dwFileSize, &dwRead, NULL) && dwRead == dwFileSize)
          {
            // Create an IStream that points to the buffer
            hr = CreateStreamOnHGlobal(hGlobal, FALSE, &pJntStream);

            if (SUCCEEDED(hr))
            {
              // Create a JournalReader object
              hr = CoCreateInstance(CLSID_JournalReader, NULL, CLSCTX_ALL, 
                          IID_IJournalReader, (void**)&pJntReader);

              if (SUCCEEDED(hr))
              {
                // Read in the JNT file by using the JournalReader
                hr = pJntReader->ReadFromStream(pJntStream, &pXmlStream);

                // Display results
                if (SUCCEEDED(hr))
                {
                  DisplayXml(pXmlStream);
                }

                // Clean up
                pXmlStream->Release();
                pJntReader = NULL;
                pJntStream->Release();
              }
            }
          }
          GlobalUnlock(hGlobal);
        }
        GlobalFree(hGlobal);
      }
    }
  }
}

Requirements

Requirement	Value
Minimum supported client	Windows XP Tablet PC Edition [desktop apps only]
Minimum supported server	None supported
Header	Journal.h (also requires journal_i.c)
DLL	Journal.dll

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