JavaScript alert with 3 buttons

Question

I have a JavaScript alert button that appears on the website when a user is going to proceed to a signup page.

It looks something like this

Would you like to proceed to the signup page?
< OK > < Cancel >

Would it be possible to add a third button to the alert so that it looks like

Would you like to proceed to the signup page?
< More Info > < OK > < Cancel >

Answer 1

Nowdays, you can use an HTML dialog element.

<dialog open>
  <p>Greetings, one and all!</p>
  <button>Ok</button><button>Maybe</button><button>Cancel</button>
</dialog>

And do what you want with it.

document.querySelectorAll('button').forEach($button => 
  $button.onclick = () => document.querySelector('dialog').removeAttribute('open'))

https://jsfiddle.net/6nus2zt4/1/

Hope this help to future generations :)

Answer 2

however you can use confirm function.. but NOT three buttons.

var r=confirm("Press a button!");
if (r==true)
  {
  x="You pressed OK!";
  }
 else
  {
  x="You pressed Cancel!";
  }