ILOS - 2013-02-27

I'd included the chatbot.php but I have a Problem. I would like to have the Chatbot response if the exact word is written.

Like if I add "Test" and write the Word "Tester" the chatbot still respondes, but it Should only responde to "Test"

//Chat bot messages
if(stristr($text, 'Test'))
"Hello World" //This is what the chatbot says when the visitor enters help me anywhere in a sentence!

I replaced stristr with in_array and pre_gmatch but it diddn't work.

Can somebody help me?