js获取ip地址

<!-- js获取ip地址 -->
<script src="http://pv.sohu.com/cityjson?ie=utf-8"></script>
<script>
//var ip=returnCitySN["cip"];
//alert(ip);
</script>
<!--此处查到的ip地址为“电信和联通互相切换”-->
<script src="http://pv.sohu.com/cityjson?ie=utf-8"></script>
<script>
alert(returnCitySN["cname"]+'ip地址是：'+returnCitySN["cip"]);
</script>