Find and set the current select option in HTML

1 < Html >
2 < Head >
3 < Meta HTTP-equiv = "Content-Type" Content = "Text/html; charset = gb2312" >
4 < Title > Untitled document </ Title >
5 < Script Language = Javascript >
6 Function Btntest_onclick ()
7 {
8 VaR Testoptions = Test. options;
9 VaR I = 0 ;
10 For (I = 0 ; I < Testoptions. length; I ++ )
11 {
12 If ( 2 = Test. Options [I]. value)
13 {
14Test. selectedindex=I
15}
16 }
17 }
18 </ Script >
19 </ Head >
20 < Body >
21 < Select Name = Test Size = 1 >
22 < Option Value = "1" > A </ Option >
23 < Option Value = "2" > B </ Option >
24 </ Select >
25 < Input Type = Button Name = Btntest Onclick = "Btntest_onclick ()" Value = "Test" >
26 </ Body >
27 </ Html >

This is also a friend's question (as long as someone asks, maybe someone else will ask, and it will be OK to send a link later)