replace several occurences in one string

[pedroz]

$string = "123-[toB][toB][toB]-567-[toB]-78-[toB][toB]";
// should echo 123-b-567-b-78-b

How can I replace the [toB] into a letter b even it is repeated?

str_replace('[toB]','b', $string);
gives me 123-bbb-567-b-78-bb

but need // 123-b-567-b-78-b

[pedroz]

something like..
preg_replace('/[toB]{2,}/','b',$string);

[johanafm]

That would require at least two occurences (from {2,} ) of [toB]. You should just match [toB] and replace each such occurence.

$p = "#\[toB]#";
$s = preg_replace($p, 'b', $string);