php 保存文件

//保存文件
            //$_SERVER['DOCUMENT_ROOT']="D:/www/"
      //$_SERVER["SCRIPT_NAME"]="/项目名/index.php"
      $www_path=$_SERVER['DOCUMENT_ROOT'];
      $save_path=explode("/",$_SERVER["SCRIPT_NAME"])[1];
      $fp=fopen($www_path.$save_path."/public/data/SalesDay.json","w+");
      fwrite($fp,json_encode($result));
      fclose($fp);