How does MFC option display the file loader function

Thanks for reaching out!
It sounds like you're looking to understand how the MFC framework handles file loading functions, particularly about displaying the Open File dialog and the classes involved, like CDocument.

To address your questions:

1. How does MFC display the Open File Dialog? - In a typical MFC application (like a multiple-document interface), you would generally see a call to DoModal() on an instance of CFileDialog, which is responsible for presenting the Open File dialog to the user.
2. Which class displays the file loader function? - The CWinApp class usually initializes this process through functions like OnFileOpen, which in turn calls CFileDialog to let users select files.
3. Is the file load function OnFileOpen? - Yes, you're correct! The OnFileOpen function is a standard handler for opening files. Within this function, you typically create a CFileDialog object and call its DoModal() method to display the dialog.

You can check the MFC documentation on files.

 Let me know if you need any further help with this. We'll be happy to assist.

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