How to Toggle a div's visibility by using a button click

Question

Below is my javascript code which i used to show a div when clicked on a button.

How can I hide it when clicked again? And then on clicking it, div should be visible again?

<script type="text/javascript">
var _hidediv = null;
function showdiv(id) {
    if(_hidediv)
        _hidediv();
    var div = document.getElementById(id);
    div.style.display = 'block';
    _hidediv = function () { div.style.display = 'none'; };
}
</script>

Answer 1

To switch the display-style between block and none you can do something like this:

function toggleDiv(id) {
    var div = document.getElementById(id);
    div.style.display = div.style.display == "none" ? "block" : "none";
}

working demo: http://jsfiddle.net/BQUyT/2/