Check if loaded inside IFrame in JavaScript

[Lampe2020]

I want to be able to easily and reliably check if a javascript is run inside an iframe, a bit like:

"
function onlyRunWhenImInsideIframe() {
    insideIframe = document.checkIfInsideIframe();
    console.log(insideIframe); // should return true or false
    if (insideIframe) { /* run other code */ }
}
"

I think it would be much easier with such a function to make a site a combined site, so if it's loaded directly it displays fully but if it's loaded inside an iframe it shows the embed version.

[Jon]

Thanks for submitting an idea to the Mozilla Connect community! Your idea is now open to votes (aka kudos) and comments.

[sfoster]

It sounds like you want window.top which lets you know this.

[Lampe2020]

I've heard window.top doesn't always work, for example when the IFrame and the page in which it's embedded aren't from the same origin, in such a case you have to do error handling and all that, so it would be easier if there was a reliable function that even works cross-origin (that would be possible because the requesting JS isn't accessing the properties of any page but only starting a function) and only returns true or false.

[jscher2000]

Mozilla isn't very likely to create new JavaScript methods that aren't part of a standard, unless there are very unusual circumstances that require it. For now, you can compare `window.self === window.top` in your pages to check the embeddedness (if that is word). For example:

https://www.jeffersonscher.com/res/xsiteframe.html