how to detect palindrom in code code example

Example 1: check if palindrome

function isPalindrome(str) {
  str = str.toLowerCase();
  return str === str.split("").reverse().join("");
}

Example 2: determine whether integer is a palindrome

public class Solution {
    public bool IsPalindrome(int x) {
        if(x < 0 || (x % 10 == 0 && x != 0)) {
            return false;
        }

        int revertedNumber = 0;
        while(x > revertedNumber) {
            revertedNumber = revertedNumber * 10 + x % 10;
            x /= 10;
        }

        return x == revertedNumber || x == revertedNumber/10;
    }
}