PHP: str_replace replaces only the first occurence

Question

for this piece of code does anyone know why only the first $unuseful word is replaced in the string?

$unuseful = array(" is ", " the ", " for ", " and ", " with "," that ", " this "," or ", ",",";","/","?","!",".");
$aux = str_replace($unuseful, " " , $statement);

"dude cost that free the dude the the "-> dude cost free dude the

"dude cost that free the dude the the the"-> dude cost free dude the the

Thanks in advance!

have a look at this answer - http://stackoverflow.com/questions/9436002/str-replace-for-distinct-word — Mukesh Soni, Jun 26 '12 at 08:40
A not-so-elegant solution would be to call the str_replace inside a loop and break until no further replacements are made. A proper solution would be to use a regex an `\b` assertions. — Salman A, Jun 26 '12 at 09:17

score 4 · Answer 1 · answered Jun 26 '12 at 08:32

4

That's because you put leading and trailing spaces.

It replaces " the " once because " the the " has only 3 spaces, and you are looking to replace 4.

answered Jun 26 '12 at 08:32

ericosg

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should use preg_replace like /(the|this|that)\s/ – Carlo Moretti Jun 26 '12 at 08:35
what is the order of replacement? Does it first replace the first occurrence and go on to the next search or find all occurrences and replace at once? – Mukesh Soni Jun 26 '12 at 08:36
but i must those empty spaces before the and after it, otherwise parts of words will be replaced – 55651909-089b-4e04-9408-47c5bf Jun 26 '12 at 08:36

score 2 · Answer 2 · 2012-06-26T08:41:39.237

2

    for($i=0;$i<count($unuseful);$i++)
    {$statement = str_replace($unuseful[$i], " " , $statement);}
$aux=$statement;

edited Jun 26 '12 at 08:41

answered Jun 26 '12 at 08:33

1

not the best solution. and there is a mistake, so only last unuseful thing will be removed from $statement and stored in $aux – Ziumin Jun 26 '12 at 08:37

score 1 · Answer 3 · answered Jun 26 '12 at 09:06

<?php
$unuseful = array('/\s+is\s+/', '/\s+the\s+/', '/\s+for\s+/', '/\s+and\s+/', '/\s+with\s+/','/\s+that\s+/', '/\s+this\s+/','/\s+or\s+/', '/,/','/;/','/\//','/\?/','/\!/','/\./');

$challenge = 'dude cost that free the dude the the';
echo preg_replace($unuseful, ' ', $challenge)."\n";
?>

gives:

dude cost free dude the

PHP: str_replace replaces only the first occurence

3 Answers3