Making a submit button create message alert

Question

I have been working on a small contact form for a webpage and I used some code from a website to create the form. My problem is that the submit button wants to post the data and all is the submit button to create a message alert, and also redirect to another page after the message appears..

Any help would be greatly appreciated! Thanks!

here is the JS:

  // Fetching HTML Elements in Variables by ID.
var x = document.getElementById("form_sample");
var createform = document.createElement('form'); // Create New Element Form
createform.setAttribute("action", ""); // Setting Action Attribute on Form
//createform.setAttribute("method", "post"); // Setting Method Attribute on Form
x.appendChild(createform);

var heading = document.createElement('h2'); // Heading of Form
heading.innerHTML = "Contact Form ";
createform.appendChild(heading);

var line = document.createElement('hr'); // Giving Horizontal Row After Heading
createform.appendChild(line);

var linebreak = document.createElement('br');
createform.appendChild(linebreak);

var namelabel = document.createElement('label'); // Create Label for Name Field
namelabel.innerHTML = "Your Name : "; // Set Field Labels
createform.appendChild(namelabel);

var inputelement = document.createElement('input'); // Create Input Field for Name
inputelement.setAttribute("type", "text");
inputelement.setAttribute("name", "dname");
createform.appendChild(inputelement);

var linebreak = document.createElement('br');
createform.appendChild(linebreak);

var emaillabel = document.createElement('label'); // Create Label for E-mail Field
emaillabel.innerHTML = "Your Email : ";
createform.appendChild(emaillabel);

var emailelement = document.createElement('input'); // Create Input Field for E-mail
emailelement.setAttribute("type", "text");
emailelement.setAttribute("name", "demail");
createform.appendChild(emailelement);

var emailbreak = document.createElement('br');
createform.appendChild(emailbreak);

var messagelabel = document.createElement('label'); // Append Textarea
messagelabel.innerHTML = "Your Message : ";
createform.appendChild(messagelabel);

var texareaelement = document.createElement('textarea');
texareaelement.setAttribute("name", "dmessage");
createform.appendChild(texareaelement);

var messagebreak = document.createElement('br');
createform.appendChild(messagebreak);

var submitelement = document.createElement('input'); // Append Submit Button
submitelement.setAttribute("type", "submit");
submitelement.setAttribute("name", "dsubmit");
submitelement.setAttribute("value", "Submit");
createform.appendChild(submitelement);

Answer 1

If I'm understanding your question correctly, you want the page to verify before submitting, correct?

If so, you can add a listener which optionally cancels the submit action.

createform.addEventListener("submit", function() {
    return confirm("Continue?");
});

Answer 2

You can add an event listener for submit event on submit button. Prevent it's default behavior, show an alert and then redirect to whatever page you want

createform.addEventListener("submit", function(e) {
e.preventDefault();
var msg = window.confirm("Want to go to other page?");
if (msg) {
    window.location.href = "url";
  }

})