[javascript] Trigger a button click with JavaScript on the Enter key in a text box

To add a completely plain JavaScript solution that addressed @icedwater's issue with form submission, here's a complete solution with form.

NOTE: This is for "modern browsers", including IE9+. The IE8 version isn't much more complicated, and can be learned here.


Fiddle: https://jsfiddle.net/rufwork/gm6h25th/1/

HTML

<body>
    <form>
        <input type="text" id="txt" />
        <input type="button" id="go" value="Click Me!" />
        <div id="outige"></div>
    </form>
</body>

JavaScript

// The document.addEventListener replicates $(document).ready() for
// modern browsers (including IE9+), and is slightly more robust than `onload`.
// More here: https://stackoverflow.com/a/21814964/1028230
document.addEventListener("DOMContentLoaded", function() {
    var go = document.getElementById("go"),
        txt = document.getElementById("txt"),
        outige = document.getElementById("outige");

    // Note that jQuery handles "empty" selections "for free".
    // Since we're plain JavaScripting it, we need to make sure this DOM exists first.
    if (txt && go)    {
        txt.addEventListener("keypress", function (e) {
            if (event.keyCode === 13)   {
                go.click();
                e.preventDefault(); // <<< Most important missing piece from icedwater
            }
        });

        go.addEventListener("click", function () {
            if (outige) {
                outige.innerHTML += "Clicked!<br />";
            }
        });
    }
});