开放平台:高德地图获取经纬度

public function real_ip()
    {
       $ip= NULL;
       if(isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
       		$arr= explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
       		$pos=  array_search('unknown',$arr);
       		if(false !== $pos) unset($arr[$pos]);
       		$ip=  trim($arr[0]);
       }elseif(isset($_SERVER['HTTP_CLIENT_IP'])) {
       		$ip= $_SERVER['HTTP_CLIENT_IP']; 
       }elseif(isset($_SERVER['REMOTE_ADDR'])) {
       	$ip= $_SERVER['REMOTE_ADDR']; 
       }
       $ip= (false !== ip2long($ip)) ? $ip : '0.0.0.0';
       return $ip;
	}