根据所在地址获取经纬度

高德地图获取经纬度

三个参数
key： https://lbs.amap.com/api/javascript-api/guide/abc/prepare注册成为开发者，申请密钥key
city： 可在https://lbs.amap.com/api/webservice/download下载城市编码表查看
address： 当前城市你要搜索的地址

示例：
http://restapi.amap.com/v3/geocode/geo?key=389880a06e3f893ea46036f030c94700&city=010&address=中宇大厦

返回结果：

{
	"status": "1",
	"info": "OK",
	"infocode": "10000",
	"count": "1",
	"geocodes": [
		{
			"formatted_address": "北京市朝阳区中宇大厦",
			"country": "中国",
			"province": "北京市",
			"citycode": "010",
			"city": "北京市",
			"district": "朝阳区",
			"township": [],
			"neighborhood": {
				"name": [],
				"type": []
			},
			"building": {
				"name": [],
				"type": []
			},
			"adcode": "110105",
			"street": [],
			"number": [],
			"location": "116.456054,39.933081",
			"level": "兴趣点"
		}
	]
}