Resize iframes cross domain for Mizmoz email previews

cross-domain-iframe-resizing.js

(function () {
    var listenForWindowHeight = function (event) {
        var parts = event.data.split('|');
        // check the message is relevant
        if (parts[0] != 'iframe-height') {
            return;
        }

        // this check is only really needed if you have multiple iframes on the same page or are experiencing message name clashes
        if (parts[1] != 'http://www.my-iframe-src.com/path') {
            return;
        }

        // change the height of my iframe
        document.getElementById('my-iframe-id').style.height = parts[2] + 'px';
    };

    // add the listener
    window.addEventListener('message', listenForWindowHeight, false);
}());