vc++实现的视图放大缩小功能，居于mfc的CScrollview

======================================================================== MICROSOFT FOUNDATION CLASS LIBRARY : ZOOMVIEW ======================================================================== AppWizard has created this ZOOMVIEW application for you. This application not only demonstrates the basics of using the Microsoft Foundation classes but is also a starting point for writing your application. This file contains a summary of what you will find in each of the files that make up your ZOOMVIEW application. ZOOMVIEW.dsp This file (the project file) contains information at the project level and is used to build a single project or subproject. Other users can share the project (.dsp) file, but they should export the makefiles locally. ZOOMVIEW.h This is the main header file for the application. It includes other project specific headers (including Resource.h) and declares the CZOOMVIEWApp application class. ZOOMVIEW.cpp This is the main application source file that contains the application class CZOOMVIEWApp. ZOOMVIEW.rc This is a listing of all of the Microsoft Windows resources that the program uses. It includes the icons, bitmaps, and cursors that are stored in the RES subdirectory. This file can be directly edited in Microsoft Visual C++. ZOOMVIEW.clw This file contains information used by ClassWizard to edit existing classes or add new classes. ClassWizard also uses this file to store information needed to create and edit message maps and dialog data maps and to create prototype member functions. res\ZOOMVIEW.ico This is an icon file, which is used as the application's icon. This icon is included by the main resource file ZOOMVIEW.rc. res\ZOOMVIEW.rc2 This file contains resources that are not edited by Microsoft Visual C++. You should place all resources not editable by the resource editor in this file. ///////////////////////////////////////////////////////////////////////////// For the main frame window: MainFrm.h, MainFrm.cpp These files contain the frame class CMainFrame, which is derived from CMDIFrameWnd and controls all MDI frame features. res\Toolbar.bmp This bitmap file is used to create tiled images for the toolbar. The initial toolbar and status bar are constructed in the CMainFrame class. Edit this toolbar bitmap using the resource editor, and update the IDR_MAINFRAME TOOLBAR array in ZOOMVIEW.rc to add toolbar buttons. ///////////////////////////////////////////////////////////////////////////// For the child frame window: ChildFrm.h, ChildFrm.cpp These files define and implement the CChildFrame class, which supports the child windows in an MDI application. ///////////////////////////////////////////////////////////////////////////// AppWizard creates one document type and one view: ZOOMVIEWDoc.h, ZOOMVIEWDoc.cpp - the document These files contain your CZOOMVIEWDoc class. Edit these files to add your special document data and to implement file saving and loading (via CZOOMVIEWDoc::Serialize). ZOOMVIEWView.h, ZOOMVIEWView.cpp - the view of the document These files contain your CZOOMVIEWView class. CZOOMVIEWView objects are used to view CZOOMVIEWDoc objects. res\ZOOMVIEWDoc.ico This is an icon file, which is used as the icon for MDI child windows for the CZOOMVIEWDoc class. This icon is included by the main resource file ZOOMVIEW.rc. ///////////////////////////////////////////////////////////////////////////// Other standard files: StdAfx.h, StdAfx.cpp These files are used to build a precompiled header (PCH) file named ZOOMVIEW.pch and a precompiled types file named StdAfx.obj. Resource.h This is the standard header file, which defines new resource IDs. Microsoft Visual C++ reads and updates this file. ///////////////////////////////////////////////////////////////////////////// Other notes: AppWizard uses "TODO:" to indicate parts of the source code you should add to or customize. If your application uses MFC in a shared DLL, and your application is in a language other than the operating system's current language, you will need to copy the corresponding localized resources MFC42XXX.DLL from the Microsoft Visual C++ CD-ROM onto the system or system32 directory, and rename it to be MFCLOC.DLL. ("XXX" stands for the language abbreviation. For example, MFC42DEU.DLL contains resources translated to German.) If you don't do this, some of the UI elements of your application will remain in the language of the operating system. /////////////////////////////////////////////////////////////////////////////