window.parent.postMessage parent check what iframe sent message

Question

I need to know what iframe sent message to the parent window, as I'll have multiple iframes on one iframe hosting page.

How can I check which of the frames sent the message?

Answer 1

You can only check which domain sent the message. If you need more identification you can always layer it into your messaging system.

Send messages like:

message = {
    "source": "menu",
    "message": "click on entry"
};

Each frame then has their own source. You will need to serialize the message, JSON works nicely.