How to detect the mouse click from browser triggered by Enter key press?

Question

I notice that on modern browsers such as Chrome, when placing one text field and one button within a form element. If enter key is pressed from the text field, the button will get clicked with a mouse click event issued by browser.

Since the only button within the form isn't used for submitting the form, is there a way for that button to only accept user click instead of browser click?

<form action="javascript:void(0)">
  <input type="text"/>
  <button id="btn">Submit</button>
</form>

var btn = document.getElementById("btn");
btn.onclick = function() {
  alert("button clicked");
}

https://codepen.io/stevenz1987/pen/poEBmqv

Answer 1

You need to assign the "type" attribute to the "button" element. Like below:

 var btn = document.getElementById("btn"); btn.onclick = function(e) { e.preventDefault(); debugger; alert(123); }

 <form action="javascript:void(0)"> <input type="text"/> <button type="button" id="btn">Submit</button> </form>

Answer 2

That doesn't happen because it's the only button in the form, but rather because it's a submit button.

<button> elements default to type="submit" when associated with a form.

To disable that behavior, set the type attribute to button manually:

<button id="btn" type="button">Submit</button>

Try it on CodePen