John Davidson

Message:

Here is the sample PHP code:

<?php

$str = '10,000.1 $100,000.1';

$pattern = '/(?!\$)\d+(,\d{3})*\.?\d*/';

$replacement_str = 'Without$sign';

echo preg_replace($pattern, $replacement_str, $str);?>

Target is to replace numbers only (i.e. "$100,000.1" should not be replaced). But the above code replaces both 10,000.1 and $100,000.1. How to achieve the exclusion?

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My Answer:
To exclude numbers that are preceded by a dollar sign, you can modify the regular expression pattern to include a negative lookbehind assertion for the dollar sign. Here is the updated code:

php
$str = '10,000.1 $100,000.1';
$pattern = '/(? $replacement_str = 'Without$sign';
echo preg_replace($pattern, $replacement_str, $str);
?>


By adding `(?