[程序报错日志](https://img-blog.csdnimg.cn/9dc31c44a2aa4001b24ea5533dcc20c1.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5bCP5LuZ5aWzJiY=,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center

因为是程序进行一定的操作才出现，一直找不到问题，最后才发现是Combobox 自定义控件的问题:控件未获得焦点时禁用鼠标滚轮事件是用的PreFilterMessage方法，
最后换了种实现方式：

protected override void WndProc(ref Message m){if (m.Msg == 522){Control currentontrol = null;currentontrol = Control.FromChildHandle(m.HWnd);bool findControlAndNotFocused = false;if (currentontrol != null){while (currentontrol.Parent != null || currentontrol == this){if (currentontrol == this){if (!currentontrol.Focused){findControlAndNotFocused = true;}break;}currentontrol = currentontrol.Parent;}}if (findControlAndNotFocused){return;}                   else{base.WndProc(ref m);}}else{base.WndProc(ref m);}            }

总结：
如若出现同样的问题，可以考虑看下自己程序的自定义控件。