// Opens the specified stream using the preview handler COM type with the provided GUID and displays the result in this PreviewHandlerHost.
public bool Open(Stream stream, Guid previewHandler)
{
UnloadPreviewHandler();
if (stream == null)
{
ErrorMessage = "No file loaded.";
return(false);
}
ErrorMessage = "";
if (previewHandler != Guid.Empty)
{
try
{
if (previewHandler != m_currentPreviewHandlerGUID)
{
m_currentPreviewHandlerGUID = previewHandler;
// need to instantiate a different COM type (file format has changed)
if (m_currentPreviewHandler != null)
{
Marshal.FinalReleaseComObject(m_currentPreviewHandler);
}
// use reflection to instantiate the preview handler type
Type _comType = Type.GetTypeFromCLSID(m_currentPreviewHandlerGUID);
m_currentPreviewHandler = Activator.CreateInstance(_comType);
}
if (m_currentPreviewHandler is IInitializeWithStream)
{
// must wrap the stream to provide compatibility with IStream
m_currentPreviewHandlerStream = stream;
StreamWrapper _wrapped = new StreamWrapper(m_currentPreviewHandlerStream);
((IInitializeWithStream)m_currentPreviewHandler).Initialize(_wrapped, 0);
}
if (m_currentPreviewHandler is IPreviewHandler)
{
// bind the preview handler to the control's bounds and preview the content
Rectangle _r = ClientRectangle;
((IPreviewHandler)m_currentPreviewHandler).SetWindow(Handle, ref _r);
((IPreviewHandler)m_currentPreviewHandler).DoPreview();
return(true);
}
}
catch (Exception _ex)
{
ErrorMessage = "Preview could not be generated.\n"; // +_ex.Message;
}
}
else
{
ErrorMessage = "No preview available.";
}
return(false);
}
// Opens the specified file using the appropriate preview handler and displays the result in this PreviewHandlerHost.
public bool Open(string filename)
{
UnloadPreviewHandler();
if (String.IsNullOrEmpty(filename))
{
ErrorMessage = "No file loaded.";
return(false);
}
// 目前64bit PDF Reader 有問題
if (isWin64AndPDF(filename))
{
ErrorMessage = "No file loaded.";
return(false);
}
// try to get GUID for the preview handler
Guid _guid = GetPreviewHandlerGUID(filename);
ErrorMessage = "";
if (_guid != Guid.Empty)
{
try
{
if (_guid != m_currentPreviewHandlerGUID)
{
m_currentPreviewHandlerGUID = _guid;
// need to instantiate a different COM type (file format has changed)
if (m_currentPreviewHandler != null)
{
Marshal.FinalReleaseComObject(m_currentPreviewHandler);
}
// use reflection to instantiate the preview handler type
Type _comType = Type.GetTypeFromCLSID(m_currentPreviewHandlerGUID);
m_currentPreviewHandler = Activator.CreateInstance(_comType);
}
if (m_currentPreviewHandler is IInitializeWithFile)
{
// some handlers accept a filename
((IInitializeWithFile)m_currentPreviewHandler).Initialize(filename, 0);
}
else if (m_currentPreviewHandler is IInitializeWithStream)
{
if (File.Exists(filename))
{
// other handlers want an IStream (in this case, a file stream)
m_currentPreviewHandlerStream = File.Open(filename, FileMode.Open);
StreamWrapper stream = new StreamWrapper(m_currentPreviewHandlerStream);
((IInitializeWithStream)m_currentPreviewHandler).Initialize(stream, 0);
}
else
{
ErrorMessage = "File not found.";
}
}
if (m_currentPreviewHandler is IPreviewHandler)
{
// bind the preview handler to the control's bounds and preview the content
Rectangle _r = ClientRectangle;
((IPreviewHandler)m_currentPreviewHandler).SetWindow(Handle, ref _r);
((IPreviewHandler)m_currentPreviewHandler).DoPreview();
return(true);
}
}
catch (Exception _ex)
{
ErrorMessage = "Preview could not be generated.\n"; // +_ex.Message;
}
}
else
{
ErrorMessage = "No preview available.";
}
return(false);
}