PHP 中的 mysqli fetch lengths函数

mysqli fetch lengths - 语法

mysqli_fetch_lengths(result);

它用于返回输出中字段的长度

mysqli fetch lengths - 返回值

如果INTEGER表示每列的大小，则返回数组；如果失败，则返回FALSE

链接：https://www.learnfk.comhttps://www.learnfk.com/php/php-mysqli-fetch-lengths.html

来源：LearnFk无涯教程网

mysqli fetch lengths - 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 * FROM emp ";
   
   if ($result=mysqli_query($connection_mysql,$sql)){
      $row=mysqli_fetch_row($result);
   
      foreach (mysqli_fetch_lengths($result) as $i=>$val){
         printf("Field %2d has length: %2d\n",$i+1,$val);
      }
   
      mysqli_free_result($result);
   }
   mysqli_close($connection_mysql);
?>