怎么设定<select>的当前值！

Question

use the selectedIndex property:<select id="something">
....
</select>
<input type="button" value="select" onclick="setSelection(1)">
<script language="javascript">
function setSelection(n)
{
  if ( (something.options.length > 0) && (n >=0) &&  (n < something.options.length) )
     something.selectedIndex = n;
}
</script>

Answer 1

<select value="hello">
<option>
………………
</select>

Answer 2

or 
<select>
<option selected>hello
…………
</select>

Answer 3

selectName.options[n].selected = true;

Answer 4

<select id=test>
<option>asdfasdf0
<option>asdfasdf1
<option>asdfasdf2
<option>asdfasdf3
<option>asdfasdf4
<option>asdfasdf5
</select>
<script>
test.options[3].selected = true;
</script>