<script language=javascript>
function check(){
var xz=document.getElementById("xz");
alert(xz.checked);
}
</script>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<input type=checkbox name="xz" id="xz" value=1>
<input type=submit name=s1 value="提交" onclick="return check();">
</html>