图片上传，获取路径

      $src=$_FILES[‘n-img‘][‘tmp_name‘];
      $file=$_FILES[‘n-img‘][‘name‘];
      $a=explode(‘.‘,$file);
      $ext=array_pop($a);
      $rand=time().mt_rand().‘.‘.$ext;
      $dst="uploadimg/{$rand}";
      if($_FILES[‘n-img‘][‘error‘]===0){
          if(move_uploaded_file($src,$dst)){
           echo "头像上传成功";
          }else{
              echo "头像未上传成功";
          }
      }