PHP 中的 mysqli fetch field direct函

mysqli fetch field direct - 语法

mysqli_fetch_field_direct(result,fieldIndex);

它用于将输出集中的下一列作为对象返回。

mysqli fetch field direct - 返回值

它返回一个包含字段定义信息的对象，如果失败，则返回FALSE

mysqli fetch field direct - 示例

<?php
   $connection_mysql=mysqli_connect("localhost","user","password","db");
   
   if (mysqli_connect_errno($connection_mysql)){
      echo "Failed to connect to MySQL: " . mysqli_connect_error();
   }
   
   $sql="SELECT Lastname FROM Persons";
   
   if ($result=mysqli_query($connection_mysql,$sql)){
      $fieldinfo=mysqli_fetch_field_direct($result,1);
      
      print $fieldinfo->name;
      print $fieldinfo->table;
      print $fieldinfo->max_length;
      
      mysqli_free_result($result);
   }
   mysqli_close($connection_mysql);
?>