<?php 
    // 此处填写你在控制台-应用管理-创建应用后获取的AK
    $ak = '您的AK';
    
    // 发起一个http get请求，并返回请求的结果
    // $url字段为请求的地址
    // $param字段为请求的参数
    function request_get($url = '', $param = array()) {
        if (empty($url) || empty($param)) {
            return false;
        }
        
        $getUrl = $url . "?" . http_build_query($param);
        $curl = curl_init(); // 初始化curl
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false); // 跳过证书检查   
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 2); // 从证书中检查SSL加密算法是否存在
        curl_setopt($curl, CURLOPT_URL, $getUrl); // 抓取指定网页
        curl_setopt($curl, CURLOPT_TIMEOUT, 1000); // 设置超时时间1秒
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); // curl不直接输出到屏幕
        curl_setopt($curl, CURLOPT_HEADER, 0); // 设置header
        $data = curl_exec($curl); // 运行curl

        if (!$data) {
            print("an error occured in function request_get(): " . curl_error($curl) . "\n");
        }

        curl_close($curl);
        
        return $data;
    }

    // 请求地址
    $url = 'https://api.map.baidu.com/reverse_geocoding/v3';
    
    // 构造请求参数
    $param['ak']   = $ak;
    $param['output']   = 'json';
    $param['coordtype']   = 'wgs84ll';
    $param['extensions_poi']   = '0';
    $param['location']   = '31.225696563611,121.49884033194';

    $res = request_get($url, $param);

    // 将原始返回的结果打印出来
    print("请求的原始返回结果为:\n");
    print($res . "\n");
?>

{
    "status": 0,
    "result": {
      "location": {
        "lng": 121.50989077799083,
        "lat": 31.22932842411674
      },
      "formatted_address": "上海市黄浦区中山南路187",
      "edz": {
        "name": ""
      },
      "business": "外滩,陆家嘴,董家渡",
      "addressComponent": {
        "country": "中国",
        "country_code": 0,
        "country_code_iso": "CHN",
        "country_code_iso2": "CN",
        "province": "上海市",
        "city": "上海市",
        "city_level": 2,
        "district": "黄浦区",
        "town": "小东门街道",
        "town_code": "310101017",
        "distance": "91",
        "direction": "东北",
        "adcode": "310101",
        "street": "中山南路",
        "street_number": "187"
      },
      "pois": [],
      "roads": [],
      "poiRegions": [],
      "sematic_description": "",
      "formatted_address_poi": "",
      "cityCode": 289
    }
  }