Using the new HTML Editing classes in MFC7

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Introduction

This article provides a bare-bones samples that demonstrates the use of the new HTML editing and browsing classes in MFC.

MFC7 includes several new classes that encapsulate the Internet Explorer MSHTML editing control. This control is an ActiveX control that provides WYSIWYG editing and browsing, and the MFC and ATL wrappers for this class make it's use very straight forward.

The sample application is a simple AppWizard generated application with the view class derived from CHtmlEditView (the last step in the MFC application wizard). In specifying CHtmlEditView as your edit class' base class, you automatically take on CHtmlEditDoc as your Document's base class as well.

These two classes work together to provide HTML file loading, saving, editing, browsing and printing. Context menus are provided and it is very simple to hook your toolbar button or menu items to the various wrapper methods in the MFC HTML editing classes.

The sample contains a rebar with two toolbars - one containing the standard load, save and cut/copy/paste buttons, and one containing formatting options such as bold, italic, indenting, hyperlink and editing mode.

In the CHtmlEditView derived class is a set of macro calls similar to the standard BEGIN_MESSAGE_MAP macros familiar to MFC programmers. In this case, though, the macros are of the form

BEGIN_DHTMLEDITING_CMDMAP(CHTMLEditView)
DHTMLEDITING_CMD_ENTRY(ID_EDIT_COPY, IDM_COPY)
DHTMLEDITING_CMD_ENTRY(ID_EDIT_CUT, IDM_CUT)
DHTMLEDITING_CMD_ENTRY(ID_EDIT_PASTE,IDM_PASTE)
DHTMLEDITING_CMD_ENTRY(ID_EDIT_UNDO, IDM_UNDO)
...
END_DHTMLEDITING_CMDMAP()

What these macros do is allow you to associate an MSHTML Command Identifier with a command ID. When the view receives the given command ID (say, ID_EDIT_COPY) it will execute the associated MSHTML command (IDM_COPY). This will in turn execute the
appropriate method of the MSHTML ActiveX control.

To associate a toolbar button with ID value ID_UNDERLINE with the MSHTML command for underlining the current selection, simply add the line

DHTMLEDITING_CMD_ENTRY(ID_UNDERLINE, IDM_UNDERLINE)

Some of the MSHTML identifiers are shown below. For a full list, consult the topic 'MSHTML Command Identifiers' in the online documentation.

If you wish to call any one of the MSHTML commands directly, then the MFC wrapper classes provide you with a number of helper functions

HRESULT ExecHelperNN(UINT nCmdID);
HRESULT ExecHelperSetVal(UINT nCmdID, LPCTSTR szID=NULL) const
HRESULT ExecHelperSetVal(UINT nCmdID, bool bValue) const
HRESULT ExecHelperSetVal(UINT nCmdID, short nNewVal) const
HRESULT ExecHelperGetVal(UINT nCmdID, bool &bValue) const
HRESULT ExecHelperGetVal(UINT nCmdID, short &nValue) const

These functions take a MSHTML Command identifier, plus an optional value (or reference for a return value) and execute the associated command.

An example is in changing the editing more to Browse:

ExecHelperNN(IDM_BROWSEMODE);

More specific wrappers are provided, such as functions to set the font face (

SetFontFace(LPCTSTR
szFace)