Send data from iframe to main window using JavaScript

We can easily send data from the iframe to the main window using the postMessage method in JavaScript.

Code in the main window

<iframe src="iframe.html">  </iframe>
<script>
    window.addEventListener('message', function(event) {
        var iframeMessage = event.data;
        console.log(iframeMessage);
    });
</script>

Code in the iframe.html file

<script>
    var message = 'Your message from iframe to main window';
    window.parent.postMessage(message, "*");
</script>