通过PHP阻止或重定向坏用户代理或机器人

Question

I found this method on stack overflow which works very good

$badAgents = array('fooAgent','blahAgent', 'etcAgent');
if(in_array($_SERVER['HTTP_USER_AGENT'],$badAgents)) {
    exit();
}

BUT

the problem is that the string needs to be perfectly match to the string inside the array.

I need to came with a new method that will ask if the user agent contains (in any part of the string) one of the strings inside the array (not exactly match just ask if it contains ONE of the characters/words inside several options inside the array)... so I came up with this :

$badAgents = array('google','libwww');

if (strpos(in_array(strtolower($_SERVER['HTTP_USER_AGENT']))), $badAgents) == true) {
    exit();
}

It's not working but I assume this it will work with small tweak.

Thanks a lot in advance guys!

Answer 1

In general, best practice is to use feature detection rather than user agent switching.

However, in this case, it seems that your parentheses placement is off. Also, I rewrote the equality to make it more clear (since some values may evaluate to FALSE).

if (strpos(in_array(strtolower($_SERVER['HTTP_USER_AGENT'])), $badAgents) !== FALSE) {
    exit();
}