Another way to do it is split the string at every occurrence of $find and then join it together using the new pattern $replace like this: 
$string = join( $replace, split($find, $string) );

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I think, this is a much neater way to do it, however I do not know how fast it is or how much more memory it uses. I have found that in JavaScript, this method works faster than the regular replace() method. Generally, working with arrays in JavaScript is always faster than working with strings. Btw could somebody do a benchmark on this to see how it compares to the other solutions?

In reply to Re: How do I replace a substring (if exists) with a different substring in a string? by harangzsolt33
in thread How do I replace a substring (if exists) with a different substring in a string? by kommesel

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