strpos returns true always in php

php, string, strpos

Solution

`strpos()` returns `FALSE` if the token was not found and the (first) position of the token in string if it was found. You need to check for boolean `FALSE` using the strict comparison operator `===` to identify if a token was found in a string or not:

if(strpos(strtolower($msg),strtolower($token)) !== false){
    echo 'ok';
} else {
    echo 'not ok';
}

This is because of PHP's loose typing system. If you use `>=0`, and the token was not found, PHP would cast the `FALSE` return value of `strpos` to `0` before the `>=` operation. And `0 >=0` evaluates to `TRUE`.

Problem

I wrote this code: ``` $token="Birth"; $msg="I am awesome and I know it"; if(strpos(strtolower($msg),strtolower($token)) >=0){ echo 'ok'; } ``` It prints `ok` As we can see there is no word like `Birth` in the message but still it returns `true`. I guess it should return `false` as the php manual says. Any help in this regard,

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