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Call this member function to invoke the WinHelp application.
Specifies additional data. The value used depends on the value of the nCmd parameter.
Specifies the type of help requested. For a list of possible values and how they affect the dwData parameter, see the WinHelp Windows function.
// Header File: HELPIDS.H // // This example header file is #include'd twice: // (1) It is #include'd by the .CPP file that passes the DWORD // context i.d. to CWinApp::WinHelp. // (2) It is #include'd in the [MAP] section of the .HPJ file, // to associate the help context string "HID_MYTOPIC" with // the help context numeric i.d., 101. // The help context string "HID_MYTOPIC" is what identifies the // help topic in the help .RTF source file, in the "#" footnote: // # HID_MYTOPIC // // Note, it is not necessary to manage help context id's this way // for help topics associated with command id's and user interface // id's defined in your RESOURCE.H file; you should use the MAKEHM // tool via the custom build rule on your resource.h file to produce // a help map (.HM) file for these id's. It is necessary to manage // help context id's as illustrated here only for help topics not // associated with command id's or user interface id's. #define HID_MYTOPIC 101 // Show the custom help topic that has the context string // "HID_MYTOPIC" in the help .RTF file, and which is mapped // to the DWORD i.d. HID_MYTOPIC in the above HELPIDS.H file. AfxGetApp()->WinHelp(HID_MYTOPIC); // The following is one line of code in the help map (.HM) // file produced by the MAKEHM tool, which is called by the custom // build rule on the resource.h file. The MAKEHM tool reads the // following #define in the application's RESOURCE.H file: // #define ID_MYCOMMAND 0x08004 // and adds a help id offset value of 0x10000 to create the // help context DWORD value 0x18004. See MFC Tech Note 28 // for more information on help id offset values. HID_MYCOMMAND 0x18004 // Rarely will you need to directly call WinHelp yourself // with the help context i.d. for a command or user interface // object. The framework will call WinHelp automatically when // the user, for example, hits F1 when the focus is on a // My Command menu item. However, if you do want to directly // call WinHelp for the help topic associated with the command, // here is how you would do it: AfxGetApp()->WinHelp(0x10000 + ID_MYCOMMAND);