VC++实现的带有tooltips提示功能的组合框控件，当组合框的内容很长时，而控件宽度比较窄时，只需将鼠标指针放在需要查看的条目上，会自动弹出一个tooltip显示该条目的完整内容。-VC++ achieved with a combination box control tooltips indicating function, when the content of the combo box is very long, while the relatively narrow width of the control, only the mouse pointer on the items to view will automatically pop up a tooltip displays the entry the full content.