dev 中的groupcontrol看起来有winform中传统铜的groupbox效果

https://supportcenter.devexpress.com/Ticket/Details/T340539/need-a-groupbox-that-looks--like-a-groupbox-and-works-with-themes

 set the UseDefaultLookAndFeel to false and the Style to Flat.
 If you do not change the default value of its BackColor property, the background color will be inherited from the immediate parent. It looks consistent with most of our skins. 

 主要修改三个属性吧：UseDefaultLookAndFeel 、Style 、BackColor