All Possible basic to advance level regex pattern example in depth example

regex-examples.php

<?php

/** EXAMPLE 1: With Digit check **/
echo "Digit Check\n-------------------\n";

// Basic Concept : /pattern/i
// / : start delimeter
// pattern : Here will be the pattern, [ eg: \d - Check if one digit match and then space ]
// i :for case insensitive [ eg: mg, mgi, i, m ]

$matches = []; // Matches array will be stored here

$string  = "123";
$pattern = "/\d\d/i"; // pattern for two digit at a same time

$is_matched = preg_match( $pattern, $string, $matches ); // Check if matched or not

print_r( $is_matched );     /** Output: 1 **/
echo "\n";
print_r( $matches );  // Print all the matches as array
/** Output: **/
// Array
// (
//     [0] => 12
// )




/** EXAMPLE 2:  **/
echo "\n-------------------\nWord Check\n-------------------\n";

$matches = []; 

$string  = "akash";
$pattern = "/\w+/i"; // w+ : w=word start, + => till upto a space/new line

$is_matched = preg_match( $pattern, $string, $matches );

print_r( $is_matched );
echo "\n";
print_r( $matches );
/** Output **/
// -------------------
// Word Check
// -------------------
// 1
// Array
// (
//     [0] => akash
// )


/** EXAMPLE 3:  **/
echo "\n-------------------\nRange Example\n-------------------\n";

$matches = []; 

$string  = "123456";
$pattern = "/[3-9]/i"; // [3-9] =>> Find one character from this range of 3 to 9

$is_matched = preg_match( $pattern, $string, $matches );

print_r( $is_matched );
echo "\n";
print_r( $matches );
/** Output **/
//-------------------
//Range Example
//-------------------
// 1
// Array
// (
//     [0] => 3
// )