Search a string replace a word with array's value

Question

The idea is to search a string for certain words and change them into something else according to specific array. Let me show you what I mean.

$string = "hello buddy, I'm your friend or maybe a fellow";      

Let's say friends is a swear word. I want to change this word to what I want. So I made this:

$swears = array(
"friend" => "fri**d",
"buddy"  => "bu**y",
"fellow" => "fe**ow"
);

I want to search the string according to the array's key and replace it with it's value. I did search the web all I get is replace a value in the array according to an array key. so after trying I came up with this:

$string = "hello buddy, I'm your friend or maybe a fellow";  

$swears = array(
"friend" => "fri**d",
"buddy"  => "bu**y",
"fellow" => "fe**ow"
);

$foreach  = $string; 
foreach($swears as $bad => $good){
$foreach       = str_replace($bad,$good,$foreach);
$filtered =  $foreach;
 }
echo $filtered;

I know it works, but is there an easy way I feel I complicated the whole thing. If I'm good, is it possible it may cause a problem, if I had large string, or take time to process it.

Answer 1

str_replace might be supplied with array of search-words and array of replacers:

<?php
$string = "hello buddy, I'm your friend or maybe a fellow";

$swears = array(
    "friend" => "fri**d",
    "buddy"  => "bu**y",
    "fellow" => "fe**ow"
);

echo str_replace(array_keys($swears), array_values($swears), $string);
?>

Shows:

hello bu**y, I'm your fri**d or maybe a fe**ow

Answer 2

the problem is that you choose to put words and replacements as keys and values in one array. A more simple way is to use 2 indexed arrays.

$words = array( 'friend', 'buddy', 'fellow' );
$replacements = array( 'fri**nd', 'bu**dy', 'fe**ow' );

$result = str_replace( $words, $replacements, $yourString );

This way you don't have to create implicitly a new array using array_keys .

If you absolutely want to store your search/replacements in an associative array, in this case don't use str_replace and use strtr :

$swears = array(
    "friend" => "fri**d",
    "buddy"  => "bu**y",
    "fellow" => "fe**ow"
);

$filtered = strtr($string, $swears);