自定义CEdit控件，只能输入0至9数字，使用时，将编辑框控件的类型改为CNumberEdit就行了，使用方便。-Customize the CEdit control, you can only enter 0 to 9 number, when used, the type of edit control changed CNumberEdit line, easy to use.

VC6,关键就是重载了void CNumberEdit::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags)，对键盘响应事件的判断。这样编辑框只接受数字-VC6, the key is a heavy void CNumberEdit:: OnChar (UINT nChar, UINT nRepCnt, UINT nFlags), on the keyboard to respond to events to judge. This edit box t