当我尝试使用 MySQLi 连接到数据库时 PHP 退出

Question

I have been developing a website recently, and I came across an error. When I tried to do print_r(error_get_last()); It output some text about mysql not being supported anymore, and to use MySQLi. I was all for it. When I edited my database class to support MySQLi, it exits every time it tries to connect. I have put echo 'hi<br />'; before and after the mysqli function, and a or trigger_error("Error: " . print_r(error_get_last())); at the end of it, but all it outputs is hi , and nothing else. My database is created in phpMyAdmin, and has all the correct permissions, but it just cannot connect. This is my connection code:

echo 'hi<br />';
$this->db = mysqli($host, $dbuser, $dbpass, $dbname) or trigger_error("Error: " . print_r(error_get_last()));
echo 'hi<br />';
$this->connect_start = microtime(true);
if ($this->db->connect_errno > 0) die ($this->debug(true));

It is in the constructor of a class that looks like this:

function db($host, $dbname, $dbpass, $dbuser)

and it is called like this:

$db = new db($host, $dbname, $dbpass, $dbuser);

Answer 1

Change this:

$this->db = mysqli() 

to

$this->db = new mysqli()

mysqli is not a function, it's a class. If you had error reporting on you'd get a message like this:

PHP Fatal error: Call to undefined function mysqli()

That's the reason why the rest of your code isn't executed, the execution stops right there.

Also note that new mysqli() will never return false , so your or ... part becomes useless. If you want to check for connection errors you have to check $this->db->connect_error after the connection attempt.