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

<form class="pure-form">
    <fieldset>
        <legend>Confirm password with HTML5</legend>

        <input type="password" placeholder="Password" id="password" required>
        <input type="password" placeholder="Confirm Password" id="confirm_password" required>

        <button type="submit" class="pure-button pure-button-primary">Confirm</button>
    </fieldset>
</form>

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;

Answer 2

Try this one ;

CSS

#indicator{
    width:20px;
    height:20px;
    display:block;
    border-radius:10px;
}
.green{
    background-color:green; 
    display:block;
}
.red{
    background-color:red;   
    display:block;
}

HTML

<form id="form" name="form" method="post" action="registration.php"> 
    <label >username : 
    <input name="username" id="username" type="text" /></label> <br>
    <label >password : 
    <input name="password" id="password" type="password" id="password" /></label>      <br>
    <label>confirm password:
    <input type="password" name="confirm_password" id="confirm_password" /><span id="indicator"></span> <br>
    </label>
    <label>
    <input type="submit" name="submit" id="regbtn"  value="registration"  />
    </label>
</form>

JQuery

$('#confirm_password').keyup(function(){
    var pass    =   $('#password').val();
    var cpass   =   $('#confirm_password').val();
    if(pass!=cpass){
        $('#indicator').attr({class:'red'});
        $('#regbtn').attr({disabled:true});
    }
    else{
        $('#indicator').attr({class:'green'});
        $('#regbtn').attr({disabled:false});
    }
});

Answer 3

WITHOUT clicking the button you will have to listen to the change event of the input fields

var confirmField = document.getElementById("confirm_password");
var passwordField = document.getElementById("password");

function checkPasswordMatch(){
    var status = document.getElementById("password_status");
    var submit = document.getElementById("submit");

    status.innerHTML = "";
    submit.removeAttribute("disabled");

    if(confirmField.value === "")
        return;

    if(passwordField.value === confirmField.value)
        return;

    status.innerHTML = "Passwords don't match";
    submit.setAttribute("disabled", "disabled");
}

passWordField.addEventListener("change", function(event){
    checkPasswordMatch();
});
confirmField.addEventListener("change", function(event){
    checkPasswordMatch();
});

then add the status element to your html:

<p id="password_status"></p>

and set the submit button id to submit

... id="submit" />

hope this helps you