PHP Regular Expression Exercise: Remove all characters from a string except a-z A-Z 0-9 or " "

Last update on December 20 2024 10:19:22 (UTC/GMT +8 hours)

Write a PHP script to remove all characters from a string except a-z A-Z 0-9 or " ".

Sample string: abcde$ddfd @abcd )der]

Visual Presentation:

Sample Solution:

PHP Code:

<?php
// Define the input string
$string = 'abcde$ddfd @abcd )der]';
// Print the old string
echo 'Old string : '.$string.'';
// Remove all characters except letters, numbers, and spaces using regular expression
$newstr = preg_replace("/[^A-Za-z0-9 ]/", '', $string);
// Print the new string after removing unwanted characters
echo 'New string : '.$newstr."\n";
?>

Output:

Old string : abcde$ddfd @abcd )der]                         
New string : abcdeddfd abcd der

Explanation:

The above PHP code takes a string as input, removes all characters except letters (both uppercase and lowercase), numbers, and spaces using a regular expression, and then prints both the original string and the modified string.

It achieves this by utilizing the "preg_replace()" function with a regular expression pattern that matches any character that is not a letter, number, or space, and replaces it with an empty string.

Finally, it prints both the original and modified strings.

Flowchart :

PHP Code Editor:

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