HtML<select>标签

<select id="selected" onchange="selectedchange()<span style="font-family: Arial, Helvetica, sans-serif;">"></span>
<option value ="volvo">Volvo</option>
<option value ="saab">Saab</option>
<option value="opel">Opel</option>
<option value="audi">Audi</option>
</select>

<script>
function : selectedChange() {
var obj = document.getElementById("selected");

var value = obj.value;

alert(value);

}
</script>