A php function that checks if string is Palindrome using OOP (Palindrome is a string that reads the same left-to-right and right-left-to-left).

palindrome.php

<?php

class Palindrome {

    public $words;
    public $regex = '/[^A-Za-z0–9]/';
    public $reserved;

    public function __construct( $words)
    {
        $this->words = $words;
    }
    public function checkPalindrome()

    {
        //remove all spaces if any
        $this->words = str_replace(' ', '', $this->words);

        //remove unwanted characters including numbers
        $this->words = preg_replace($this->regex, '', $this->words);

        //convert word to lower case
        $this->words = strtolower($this->words);

        //reverse the word for comparison
        $this->reversed = strrev($this->words);

        //compare word(s) and reserved word(s)
        if($this->words == $this->reversed){
            return true;
        } else {
            return false;
        }
    }
}

//instantiate object
$word = new Palindrome('aadaa');
//call function
$words->checkPalindrome(); //Output: True

//instantiate object
$word2 = new Palindrome('another');
//call function
$word2->checkPalindrome(); //Output: False