Communication parent and child iframe

receive-data.js

window.addEventListener('message', function(e) {
    // Get the sent data
    const data = e.data;
    
    // If you encode the message in JSON before sending them, 
    // then decode here
    // const decoded = JSON.parse(data);
});

send-data.js

// how to send data

// 1. from child iframe to parent
const message = JSON.stringify({
    message: 'Hello from iframe',
    date: Date.now(),
});
window.parent.postMessage(message, '*');


// 2. from parent to child
// this sample with jquery you can use native js with modify
$("iframe").contentWindow.postMessage(message, '*');