Internet Explorer plays a little click sound when the location of a page changes. This is a great usability feature as it lets the user know that something is happening. However, this little click sound can become really annoying with web applications that make extensive use of iframes. For example, imagine an application using several iframes to sandbox untrusted third party ads. Refreshing the content of the iframes (by changing their src attribute) makes the application sound like an automatic rifle. Scary, huh? Well, I recently found out about a very clever trick that can make this click sound go away.

Replace:

iframe.src = "...";

by:

var newIFrame = document.createElement("iframe");
newIFrame.src = "...";
iframe.parentNode.replaceChild(newIframe, iframe);

The secret is to set the iframe src attribute before appending it to the document… However, this simple approach exhibits a very unpleasant flickering. The following snippet shows how to get rid of the flickering as well:

function setIFrameSrc(iframe, src) {
    var el;
    iframe = YAHOO.util.Dom.get(iframe);
    if (YAHOO.env.ua.ie) {
        // Create a new hidden iframe.
        el = iframe.cloneNode(true);
        el.style.position = "absolute";
        el.style.visibility = "hidden";
        // keep the original iframe id unique!
        el.id = "";
        // Listen for the onload event.
        YAHOO.util.Event.addListener(el, "load", function () {
            // First, remove the event listener or the old iframe
            // we intend to discard will not be freed...
            YAHOO.util.Event.removeListener(this, "load", arguments.callee);
            // Show the iframe.
            this.style.position = "";
            this.style.visibility = "";
            // Replace the old iframe with the new one.
            iframe.parentNode.replaceChild(this, iframe);
            // Reset the iframe id.
            this.id = iframe.id;
        });
        // Set its src first...
        el.src = src;
        // ...and then append it to the body of the document.
        document.body.appendChild(el);
    } else {
        iframe.src = src;
    }
}

This example demonstrates this technique (turn the volume up, and open it up with Internet Explorer) Note: the navigation sound you hear when using Internet Explorer (or Windows Explorer) can be configured via the Sounds dialog accessible from the Control Panel.

Update: I forgot to mention that, by using this trick, you will break the back / forward navigation buttons. Therefore, this trick should only be used for a non-navigational purpose only.