Type-Safe Access to Controls in a Dialog Box
The controls in a dialog box can use the interfaces of MFC control classes such as CListBox and CEdit. You can create a control object and attach it to a dialog control. Then you can access the control through its class interface, calling member functions to operate on the control. The methods described here are designed to give you type-safe access to a control. This is especially useful for controls such as edit boxes and list boxes.
There are two approaches to making a connection between a control in a dialog box and a C++ control member variable in a CDialog-derived class: