Application Modernization: What Is It and How to Get Started
I wrote really simple color syntax editor based on RICHEDIT control. I spent only one day on this work (ok one and half), so it's far from ideal, but the result is suitable for editing small scripts in VBScript or JScript (this is a part of my work on a script host application)..
How to use this control:
- Insert a RICHEDIT control into a dialog resource. Add a member variable to appropriate the CDialog or CFormView derived class and subclass the control in the OnInitDialog function. Or create the CTWScriptEdit control then you need it.
- To minimize any flickering set the style of the parent window (usually the dialog) to WS_CLIPCHILDREN.
- Call the Initialize() method of the CTWScriptEdit. (This sets default attributes of the text).
How to set parameters of the language:
- void SetCaseSensitive(BOOL bSensitive);
Is language case sensitive?
- void SetChangeCase(BOOL bChange);
Force case for keywords?
- void SetSLComment(TCHAR chComment, TCHAR chComment2 = 0);
Set character(s) for comment ('\'' for VBScsipt, '\\', '\\' for JScript)
- void SetSLComment(LPCTSTR lpszComment);
Set keyword for comment ("Rem" for VBScript) must be in the keyword list too
- void SetStringQuotes(LPCTSTR lpszStrQ);
Determines string quotation character(s) ("\"")
- void AddKeywords(LPCTSTR lpszKwd);
- void AddConstants(LPCTSTR lpszKwd);
- void SetKeywordColor(COLORREF clr, BOOL bBold);
Sets color and bold attribute for keywords
- void SetConstantColor(COLORREF clr, BOOL bBold);
Sets color and bold attribute for constants
- void SetCommentColor(COLORREF clr, BOOL bBold);
Sets color and bold attribute for comment
- void SetNumberColor(COLORREF clr, BOOL bBold);
Sets color and bold attribute for numbers
- void SetStringColor(COLORREF clr, BOOL bBold);
Sets color and bold attribute for strings
Comments on the Source Code:
The Interesting code sits in the CTWScriptEdit control (TWScriptEdit.h and TWScriptEdit.cpp). This control is derived from CRichEditCtrl. The whole miracle occurs in the EN_PROTECTED and EN_CHANGE notification handlers. All text in the control has the CFE_PROTECTED flag, so before any change the OnProtected handler is called. After the change, the OnChange handler is called. This enables us to determine the affected lines that need reformatting. Real formatting occurs in FormatTextRange() which parses the range of text and changes necessary attributes by calling helper functions. The control correctly handles WM_SETTEXT and EM_RELACELSEL, so it's possible to change text programmatically.
The Undo buffer is affected during formatting, so the undo function works incorrectly.
Pasting RTF text from clipboard into the control retains font, size and others attributes of pasted text. This can be corrected in SetFormatRange() method - just check and change all attributes.
I am sure that I am better at the C++ language than in English, so my description is short, but I hope that source code answers all your questions.
Added VBScriptEditor project shows how to implement coloring features in CRichEditView derivation.