How to limit number of characters replaced using preg_replace

[jimmygee]

Hi,

 

I am using the following preg_replace to change all instances of "His" to "You", "Her" to "You", and "You" to "We".

 

$patterns[0] = '/His/';

$patterns[1] = '/Her/';

$patterns[2] = '/You/';

$replacements[2] = 'Your';

$replacements[1] = 'Your';

$replacements[0] = 'We';

echo preg_replace($patterns, $replacements, $oldstring);

 

 

My problem is that not only is the preg_replace function changing "You" to "We", it is also changing "Your" to "Wer".

 

How do I modify my code so that it changes "You" to "We" but not "Your" to "Wer"?

 

Thank you for your help.

 

Jimmy

 

[salathe]

A common solution is to use the \b magical escape sequence which matches only at word boundaries, to quote the bible, "A word boundary is a position in the subject string where the current character and the previous character do not both match \w or \W (i.e. one matches \w and the other matches \W), or the start or end of the string if the first or last character matches \w, respectively." (\w matches a "word" character).

 

E.g. /\bYou\b/ will match "You" in "You are awesome" but not "Yours sincerely"

[jimmygee]

Infinite gratitude. It works perfectly.

 

It would have taken a PHP newbie weeks to figure that out by myself.

 

Thanks again.

[salathe]

You're welcome, we're here to help; even if it's just knowing where to look. 

 

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