这里有例子:
VSNetToolbar (flat toolbar with embedded combo boxes) written in C#
http://www.codeproject.com/cs/menu/vsnettoolbar.asp
VSNetToolbar (flat toolbar with embedded combo boxes) written in C#
http://www.codeproject.com/cs/menu/vsnettoolbar.asp
http://www.vbaccelerator.com/home/VB/Code/Controls/Toolbar/vbAccelerator_ToolBar_and_CoolMenu_Control/article.asp