<body>
<select >
<option value="1">1</option>
<option value="2" selected="">2</option>
<option value="3">3</option>
</select>
<button >test</button>
<script>
function getDefaultSelectedOption(selectId, valIfNull) {
var dom, selectId = (/^#/, ''), opts;
try {
opts = (selectId).getElementsByTagName('option');
for (var i in opts) {
if (opts[i].defaultSelected) {
dom = opts[i];
break;
}
}
} catch (e) {
}
return dom||valIfNull;
}
</script>
<script>
('btn').onclick = function () {
alert((getDefaultSelectedOption('sel1', {})).value);
};
</script>
</body>