摘要：
AlwaysVisibleControlExtender控件：该控件的最直观的效果就是无论你如何拖动滚动条还是拖拽浏览器窗口大小，该控件都会随之变化或者说始终复位到浏览器窗口的固定位置。
(AlwaysVisibleControlExtender used to add constant visibility to an ASP.NET control. The control that is extended then always moves to fixed position in the page regardless of how the body is resized or scrolled.) 阅读全文
