Make selected item in the listbox always at the top.

When i call a function , select a item in the list .but i want that selected move to the top of the list automatically, instead of click the scroolbar.

Can I do this Thank you.

I found this link ,  but i cant control the event scrolling. :(

http://www.codeproject.com/cs/combobox/ScrollingListbox.asp

This is my code , when i click button, the scrollbar move to new value 48.But it not works !

private void button1_Click(object sender, System.EventArgs e)

this.scrollingListBox1_Scrolled(

this.scrollingListBox1,

new System.Windows.Forms.ScrollEventArgs(System.Windows.Forms.ScrollEventType.EndScroll,48)

);