String Reverse

Adds a reverse function to the String prototype.

HTML

<input id="text" type="text" placeholder="Enter some text"></input>
<button id="reverse">Reverse</button>
<div id="answer"></div>

JavaScript

String.prototype.reverse = function(){
    var orig = this;
    var reverse = '';
    while(orig!=''){
        reverse += orig.substr(orig.length-1);
        orig = orig.substr(0, orig.length-1);
    }
    return reverse;
}

function showReverse(){
    var rev = (document.getElementById('text').value.reverse());
    document.getElementById('answer').innerHTML = rev;
}

document.getElementById('reverse').onclick = showReverse;