php - substr not working correctly? -

php - substr not working correctly? -

i creating forum, , working on bbcode section. bbcode works, implementing emoticon system. syntax looks this: [e]:)[/e]

i made string testing purposes:

[b]hello world[/b] [i]i having fun[/i] [e]:)[/e] how doing today?! <3[color=blue]:d[/color]

and returning not want. here returning:

:)[/e] how doing today?! <3[color=bl

this code:

function bbcode($str) { if (strpos($str, '[e]')!==false && strpos($str, '[/e]')!==false) { $f = strpos($str, '[e]') + 3; $s = strpos($str, '[/e]'); $emote = substr($str, $f, $s); } homecoming $emote; }

note $f , $s returning right positions, 45 , 47, substr not cutting string correctly. why , how can prepare it?

"string substr ( string $string , int $start [, int $length ] )

returns portion of string specified start and length parameters."

$emote = substr($str, $f, $s - $f);

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