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PHP

Pontus Bolmér
Pontus Bolmér
12,471 Points
Posted by Pontus Bolmér
Pontus Bolmér
12,471 Points

Regexp PHP

Im having a question regarding regExp php, i would be very happy if anyone knows the answer to my question.

If im doing the preg_replace function

$numbes = "abc123def";

$numbes = preg_replace("/\d/","897",$numbes);

it gives me the answerr "We love Mankeysabc897897897def"

but if i add i + sign after the d it just gives me one change.

If i add the * it gives me the answer"We love Mankeys897a897b897c897897d897e897f897"

My question is, why does only add in 897 once with the + sign, and with out any + or * it adds several, and with the * it adds so many.

I know it's a wierd question, but im really searcing for a answer.

1 Answer

Robert Anthony
Robert Anthony
19,952 Points
Robert Anthony
Robert Anthony
19,952 Points

The \d on its own matches any single digit, so replaces each 1,2,3 with 897.

The \d+ matches one or more digits so it matches the 123 and replaces the group with 897

The \d* matches zero or more digits so the gap between every character matches and is replaced by 897 and the 123 matches so is also replaced by 897