var returnCitySN = {"cip": "123.154.164.100", "cid": "330300", "cname": "浙江省温州市"};

//pv.sohu.com/cityjson?ie=utf-8

搜狐、新浪、百度、腾讯API
方法一搜狐api
<script src="http://pv.sohu.com/cityjson?ie=utf-8"></script>  
console.log(returnCitySN)  //返回对象Object {cip: "122.70.200.146", cid: "110000", cname: "北京市"}

方法二新浪api
<script src="http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=js"></script>
var msg = remote_ip_info;console.log(msg)//返回对象Object {ret: 1, start: -1, end: -1, country: "中国", province: "北京",city: "北京"…}   

方法三新浪apijsonp
<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
$.getScript('http://int.dpool.sina.com.cn/iplookup/iplookup.php?format=js', function(_result) {
if (remote_ip_info.ret == '1') {
console.log('国家' + remote_ip_info.country +'n省' + remote_ip_info.province + 'n市' + remote_ip_info.city + 'n区' + remote_ip_info.district + 'nISP' + remote_ip_info.isp + 'n类型' + remote_ip_info.type + 'n其 ' + remote_ip_info.desc);
//国家中国省北京市北京区ISP类型其
} else {
alert('没有找到匹配的IP地址信息！');
}
});

方法四百度地图api
function showLocation(data) {console.log(data.content.address_detail.city);}
$.getScript("http://api.map.baidu.com/location/ip?ak=百度地图密匙&callback=showLocation");


方法四腾讯地图api
$.getScript('https://apis.map.qq.com/ws/location/v1/ip?callback=showLocation&key=腾讯地图密匙&output=jsonp')；
function showLocation(data) {console.log(data.result.ad_info.city)}