PHP mysqli_fetch_lengths() 函数

<?php
// 假定数据库用户名：root，密码：123456，数据库：codingdict
$con=mysqli_connect("localhost","root","123456","codingdict");
if (mysqli_connect_errno($con))
{
    echo "连接 MySQL 失败: " . mysqli_connect_error();
}

$sql="SELECT name,url FROM websites ORDER BY alexa";


if ($result=mysqli_query($con,$sql))
{
    $row=mysqli_fetch_row($result);

    // 显示字段长度
    foreach (mysqli_fetch_lengths($result) as $i=>$val)
    {
        printf("字段 %2d 长度为: %2d",$i+1,$val);
        echo "<br>";
    }

    // 释放结果集
    mysqli_free_result($result);
}

mysqli_close($con);
?>

mysqli_fetch_lengths( _result_ ) _;_