Javascript判断多选框checkbox和单选钮是否选中

//第几个没有选
<input type="checkbox" name="checkbox1" checked>
<input type="checkbox" name="checkbox1">
<input type="checkbox" name="checkbox1" checked>
<input type="checkbox" name="checkbox1">
<input type="checkbox" name="checkbox1">
<script language=javascript>
function check(obj)
</script>
<input type=button onclick="check('checkbox1')" value="检测">

//一个也没有选

<input type="checkbox" name="test">
<input type="checkbox" name="test">
<input type="checkbox" name="test">
<input type="checkbox" name="test">
<input type="checkbox" name="test">
<Script Language="JavaScript">
</Script>
<input type=button onclick="check('test');" value="检测">

<script language="javascript">
function checkme()

</script>