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Q116491: PRB: ClassWizard Links Only Types with DDX Support

Article: Q116491
Product(s): Microsoft C Compiler
Version(s): 1.5,1.51,1.52,2.0,2.1,4.0,5.0
Operating System(s): 
Keyword(s): kbwizard kbMFC kbVC150 kbVC200 kbVC400 kbVC500 kbVC600 kbClassWizard kbGrpDSTools
Last Modified: 15-FEB-2002

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The information in this article applies to:

- The ClassWizard, used with:
   - Microsoft Visual C++, versions 1.5, 1.51, 1.52 
   - Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 4.0 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
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SYMPTOMS
========

By default, ClassWizard allows linking the edit controls of combo boxes only to
member variables that are of type CString.

MORE INFORMATION
================

By design, ClassWizard allows links only to types for which dynamic data
exchange (DDX) routines have been provided. Microsoft Foundation Classes (MFC)
provides a DDX_FieldCBString() function to manage data transfer between the edit
control of a combo box and a CString member variable, but not between combo
boxes and other types (for example, there is no DDX_FieldCBInt). This is not a
problem with ClassWizard; it is simply a matter of providing support for those
DDX routines that are available.

If a particular routine that you would find useful does not already exist, you
can create a custom routine. "MFC Technical Note #26" provides instructions on
how to create custom DDX/DDV routines. Once a custom routine is provided,
ClassWizard recognizes the type and allows the mapping to be made. This
additional functionality may be useful when linking the edit controls of combo
boxes to non-CString fields, such as those found in a database.

Additional query words: kbinf

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Keywords          : kbwizard kbMFC kbVC150 kbVC200 kbVC400 kbVC500 kbVC600 kbClassWizard kbGrpDSTools 
Technology        : kbVCsearch kbAudDeveloper kbClassWizard
Version           : :1.5,1.51,1.52,2.0,2.1,4.0,5.0
Issue type        : kbprb

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