how to check confirm password field in form without reloading page

Question

I have a project in which I have to add a registration form and I want to to validate that the password and confirm fields are equal without clicking the register button.

Answer 1

I think this example is good to check https://codepen.io/diegoleme/pen/surIK

I can quote code here

    

        
Confirm password with HTML5

        
        

        Confirm
    

and

var password = document.getElementById("password")
  , confirm_password = document.getElementById("confirm_password");

function validatePassword(){
  if(password.value != confirm_password.value) {
    confirm_password.setCustomValidity("Passwords Don't Match");
  } else {
    confirm_password.setCustomValidity('');
  }
}

password.onchange = validatePassword;
confirm_password.onkeyup = validatePassword;