包含了以下功能：
(1)通过IP地址获取城市地址（并不完全准确，存在代理IP或IP中转时定位与实际位置不一致的情况）
(2)通过移动端浏览器及GPS定位位置坐标
(3)根据位置坐标转换百度地图坐标
(4)根据位置坐标逆推城市具体地址功能（存在一定误差）
(5)通过使用百度API展示地理位置及添加标注功能
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>地理位置测试</title>
<script type="text/javascript" src="http://api.map.baidu.com/api?v=1.3"></script>
<script type="text/javascript"
src="http://developer.baidu.com/map/jsdemo/demo/convertor.js"></script>
<script type="text/javascript">
var map;
var gpsPoint;
var baiduPoint;
var gpsAddress;
var baiduAddress;
function getLocation() {
//根据IP获取城市
var myCity = new BMap.LocalCity();
myCity.get(getCityByIP);
//获取GPS坐标
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(showMap, handleError, {
enableHighAccuracy: true, maximumAge: 1000 });
} else {
alert("您的浏览器不支持使用HTML 5来获取地理位置服务");
}
}
function showMap(value) {
var longitude = value.coords.longitude;
var latitude = value.coords.latitude;
map = new BMap.Map("map");
//alert("坐标经度为：" + latitude + "， 纬度为：" + longitude );
gpsPoint = new BMap.Point(longitude, latitude); // 创建点坐标
map.centerAndZoom(gpsPoint, 15);
//根据坐标逆解析地址
var geoc = new BMap.Geocoder();
geoc.getLocation(gpsPoint, getCityByCoordinate);
BMap.Convertor.translate(gpsPoint, 0, translateCallback);
}
translateCallback = function (point) {
baiduPoint = point;
var geoc = new BMap.Geocoder();
geoc.getLocation(baiduPoint, getCityByBaiduCoordinate);
}
function getCityByCoordinate(rs) {
gpsAddress = rs.addressComponents;
var address = "GPS标注：" + gpsAddress.province + "," + gpsAddress.city + "," +
gpsAddress.district + "," + gpsAddress.street + "," + gpsAddress.streetNumber;
var marker = new BMap.Marker(gpsPoint); // 创建标注
map.addOverlay(marker); // 将标注添加到地图中
var labelgps = new BMap.Label(address, { offset: new BMap.Size(20, -10) });
marker.setLabel(labelgps); //添加GPS标注
}
function getCityByBaiduCoordinate(rs) {
baiduAddress = rs.addressComponents;
var address = "百度标注：" + baiduAddress.province + "," + baiduAddress.city + ","
+ baiduAddress.district + "," + baiduAddress.street + "," + baiduAddress.streetNumber;
var marker = new BMap.Marker(baiduPoint); // 创建标注
map.addOverlay(marker); // 将标注添加到地图中
var labelbaidu = new BMap.Label(address, { offset: new BMap.Size(20, -10) });
marker.setLabel(labelbaidu); //添加百度标注
}
//根据IP获取城市
function getCityByIP(rs) {
var cityName = rs.name;
alert("根据IP定位您所在的城市为:" + cityName);
}
function handleError(value) {
switch (value.code) {
case 1:
alert("位置服务被拒绝");
break;
case 2:
alert("暂时获取不到位置信息");
break;
case 3:
alert("获取信息超时");
break;
case 4:
alert("未知错误");
break;
}
}
function init() {
getLocation();
}
window.onload = init;
</script>
</head>
<body>
<div id="map" style="width:600px;height:600px;"></div>
</body>
</html>
原文：http://www.cnblogs.com/blgg/p/5062677.html