Adding comma as thousands separator (javascript) - output being deleted instead
<p>I am attempting to dynamically adjust a numerical value entered to include thousand separators</p>

<p>Here is my code:</p>

<pre><code>function addCommas(nStr) {
    nStr += '';
    x = nStr.split('.');
    x1 = x[0];
    x2 = x.length &gt; 1 ? '.' + x[1] : '';
    var rgx = /(\d+)(\d{3})/;
    while (rgx.test(x1)) {
        x1 = x1.replace(rgx, '$1' + ',' + '$2');
    }
    return x1 + x2;
}


&lt;input type="number"  onkeyup="this.value=addCommas(this.value);" /&gt;
</code></pre>

<p>However when I enter numbers after the 4 one, the field is cleared.</p>

<p>Any ideas where I am going wrong? If there is a jQuery solution I'm already using that on my site.</p>
