【PHP】PHP地理位置计算

    <?php
    /**
    *求两个已知经纬度之间的距离,单位为米
    *@param lng1,lng2 经度
    *@param lat1,lat2 纬度
    *@return float 距离，单位米
    **/
    function getdistance($lng1,$lat1,$lng2,$lat2){
    //将角度转为狐度
    $radLat1=deg2rad($lat1);//deg2rad()函数将角度转换为弧度
    $radLat2=deg2rad($lat2);
    $radLng1=deg2rad($lng1);
    $radLng2=deg2rad($lng2);
    $a=$radLat1-$radLat2;
    $b=$radLng1-$radLng2;
    $s=2*asin(sqrt(pow(sin($a/2),2)+cos($radLat1)*cos($radLat2)*pow(sin($b/2),2)))*6378.137*1000;
    return intval($s);
    }
    
    function distanceConvert($s){
    $s = intval($s);
    if($s <= 0){
    return '附近';
    }elseif($s > 0 && $s <= 1000){
    return $s.'m';
    }elseif($s > 1000 && $s <= 2000){
    return '<2km';
    }elseif($s > 2000 && $s <= 3000){
    return '<3km';
    }elseif($s > 3000 && $s <= 4000){
    return '<4km';
    }elseif($s > 4000 && $s <= 5000){
    return '<5km';
    }elseif($s > 5000){
    return '>5km';
    }
    }
    
    /**
    * 根据条件获取商户列表
    * @param string $lng
    * @param string $lat
    * @param string $city_id
    * @param string $district_id
    * @param string $type_id
    * @param string $search
    * @return mixed
    */
    //如果存在经纬度则考虑范围5公里内数据，如果不存在经纬度，则不考虑
    public function GetShopList($navigationId = 0,$page = 1,$size =10 ,$lng = '', $lat ='', $city_id = '',$district_id = '',$type_id = '',$search = '')
    {
    $field = 'id,province_id,city_id,district_id,navigation_id,type_id,name,phone,address,logo,stime,etime,rule,activity,discount,latitude,longitude,status,token,sort,description,gmt_created';
    
    $where = array(
    'is_deleted' => 0,
    'is_show' => 1,
    'navigation_id'=>$navigationId,
    );
    
    //判断城市，县区，分类是否存在
    if(!empty($city_id)){
    $where['city_id|province_id'] = $city_id;
    }
    if(!empty($district_id)){
    $where['district_id'] = $district_id;
    }
    if(!empty($type_id)){
    $where['type_id'] = $type_id;
    }
    if(!empty($search)){
    $where['name'] = array('like',"%{$search}%");
    }
    
    $offset = ($page * $size) - ($size - 1);
    //如果存在经纬度，就根据经纬度查询5公里范围内数据
    if(!empty($lng) && !empty($lat))
    {
    // //求出半径
    // $radius = 5;//半径范围，单位km
    // $rangeLat = 180 / pi() * $radius / 6372.797;//纬度范围
    // $rangeLng = $rangeLat / cos($lat * pi() / 180.0); //经度范围
    // $maxLat = $lat + $rangeLat; //x1
    // $minLat = $lat - $rangeLat; //x0
    // $maxLng = $lng + $rangeLng; //y1
    // $minLng = $lng - $rangeLng; //y0
    //
    // $where['latitude'] = array(array('lt',$maxLat),array('gt',$minLat));
    // $where['longitude'] = array(array('lt',$maxLng),array('gt',$minLng));
    
    $list = $this->where($where)->field($field)->order("abs(longitude - {$lng}) + abs(latitude - {$lat})")->limit($offset,$size)->select();
    }else{
    $list = $this->where($where)->field($field)->order('sort asc')->limit($offset,$size)->select();
    }
    
    //记录错误日志
    if ($list === false) {
    wLog('GetShopList error! sql:' . $this->getLastSql(), $this->errorFile);
    wLog('GetShopList error! errorInfo:' . $this->error, $this->errorFile);
    }
    //wLog('GetShopList sql:' . $this->getLastSql(), $this->errorFile);
    return $list;
    }