connect errno - 语法
mysqli_connect_errno();
它返回上次连接的错误代码
connect errno - 返回值
它返回错误代码值,否则给出0
connect errno - 示例
<?php $connection=mysqli_connect("localhost","wrong_user","wrong_pass","wrong_db");if (!$connection){ die("Connection error: " . mysqli_connect_errno()); } ?>