My website will be used as an iframe on another website. My intention is to create a variable on google tag manager that will detect if the traffic I'm receiving is coming from a normal source or from a website with my iframe on it. I came up with this, but I don't think it could be correct.

function inIframe () {
    try {
        return window.self !== window.top;
    } catch (e) {
        return true;
    }
}