PHP Regular Expression Exercises: Remove nonnumeric characters except comma and dot

Last update on May 31 2025 12:56:46 (UTC/GMT +8 hours)

4. Remove nonnumeric characters except comma and dot

Write a PHP script to remove nonnumeric characters except comma and dot.

Sample string : '$123,34.00A'

Visual Presentation:

PHP Regular Expression Exercise: Remove nonnumeric characters except comma and dot

Sample Solution:

PHP Code:

<?php
// Define a string containing alphanumeric characters, including special characters like comma and period.
$str1 = "$12,334.00A";

// Use preg_replace function to remove all characters except digits (0-9), comma (,), and period (.).
// The regular expression pattern "/[^0-9,.]/" matches any character that is not a digit, comma, or period.
// The replacement parameter is an empty string, effectively removing all non-digit, comma, and period characters.
echo preg_replace("/[^0-9,.]/", "", $str1)."\n";
?>

Output:

12,334.00

Explanation:

In the exercise above,

The given PHP code removes all characters except digits (0-9), comma (,), and period (.) from the string '$str1'.

It uses the 'preg_replace' function with a regular expression pattern '"/[^0-9,.]/"' to match any character that is not a digit, comma, or period, and replaces those characters with an empty string.

Finally, it echoes the modified string.

Flowchart :

For more Practice: Solve these Related Problems:

Write a PHP function that extracts a valid monetary value from a mixed-character string preserving comma as thousand separator and dot as decimal.
Write a PHP script to remove all nonnumeric characters from a string except dots, commas, and minus signs (for negative numbers).
Write a PHP script that removes all characters except digits, commas, and dots, then validates the result as a proper floating-point number.
Write a PHP function to clean up a string by removing all non-digits, while preserving one comma for thousands and one dot for decimal position.

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PHP Code Editor:

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