I have a string "Hello World !" and I want to replace some letters in it and receive result like "He!!! W!r!d !" it's means that i changed all "l" and "o" to "!" I found function preg_replace();
function replace($s){
return preg_replace('/i/', '!', "$s");
}
and it works with exactly one letter or symbol, and I want to change 2 symbols to "!".