2 - 1108. Defanging an IP Address

https://leetcode.com/problems/defanging-an-ip-address/

var defangIPaddr = function(address) {
  let defangStr = '';
  for (let i = 0; i < address.length; i++) {
      if (address[i] === '.') {
        defangStr += '[.]';
      } else {
        defangStr += address[i]
      }
  }
  return defangStr;
};

there are some convenient api

var defangIPaddr = function(address) {
  return address.split('.').join('[.]');
};

var defangIPaddr = function(address) {
    return address.replace(/\./g,"[.]");
};