run regex expressins php code example

Example 1: preg_match in php

<?php
//Syntex : int preg_match( $pattern, $input, $matches, $flags, $offset)
  
// Declare a variable and initialize it 
$str = "Check For Testing."; 
  
// case-Insensitive search for the word "Check" 
if (preg_match("/\bCheck\b/i", $str, $match))  
    echo "Matched!"; 
else
    echo "not matched";   
  

// Output : Matched
?>

Example 2: php regular expression

Modifier	Description
i 	Makes the match case insensitive
m 	Specifies that if the string has newline or carriage
	return characters, the ^ and $ operators will now
	match against a newline boundary, instead of a
	string boundary
o 	Evaluates the expression only once
s 	Allows use of . to match a newline character
x 	Allows you to use white space in the expression for clarity
g 	Globally finds all matches
cg 	Allows a search to continue even after a global match fails