PHP mysqli_fetch_lengths () function

PHP MySQLi Reference Manual

Return result set field length:

<?php 
// 假定数据库用户名：root，密码：123456，数据库：w3big 
$con=mysqli_connect("localhost","root","123456","w3big"); 
if (mysqli_connect_errno($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);
?>

Definition and Usage

mysqli_fetch_lengths () function returns the result set field length.

grammar

technical details