Copy div from parent website to a textarea in iframe

问题

In the Google Translator I've made a second instance of Google Translate with

var makediv = document.createElement("secondinstance"); makediv.innerHTML = '<iframe id="iframenaturalID" width="1500" height="300" src="https://translate.google.com"></iframe>'; makediv.setAttribute("id", "iframeID"); var getRef = document.getElementById("gt-c"); var parentDiv = getRef.parentNode; parentDiv.insertBefore(makediv, getRef); 

And I'm trying to copy text from auto-correction of the first instance to the textarea of the second instance:

I'm trying this (this code works if I just copy html within the Chrome inspector{using [0] or [1] to select elements with the same IDs}, however it's only possible to use two instances of the translator with iframe embedding):

setInterval(function() {     var childAnchors1 = window.parent.document.querySelectorAll("#spelling-correction > a");     var TheiFrameInstance = document.getElementById("iframeID");     TheiFrameInstance.contentWindow.document.querySelectorAll("#source").value = childAnchors1.textContent; }, 100); 

But the console says that it cannot read property "document" of undefined at eval, and says that the problem is in this line:

  TheiFrameInstance.contentWindow.document.querySelectorAll("#source").value = childAnchors1.textContent; 

I've tried embedding another website, and it also didn't work. I also tried to call iframe by "iframenaturalID", and tried to write TheiFrameInstance.contentWindow.document.querySelectorAll without the contentWindow, but nothing seems to work. I would very much appreciate any help.

回答1:

Had similar problem recently trying to access iframe. Unfortunately it is impossible IF it is a cross-domain. Read more: Get element from within an iFrame

Hope it helps.

回答2:

Ok, I made it work with a different method of creating iframe:

var a = document.createElement('iframe'); a.src = "https://translate.google.com";  a.id = "iframenaturalID"; a.width = "1000"; a.height = "500"; document.querySelector('body').appendChild(a) 

And (copying textcontent from the correction div to the iframe textarea):

let iframe = document.getElementById("iframenaturalID"); setInterval(function() { let source = iframe.contentWindow.document.getElementById("source"); let destination = window.parent.document.querySelector("#spelling-correction > a");   source.value = destination.textContent;      }, 100); 

Now it does what I tried to do, however I still get mistake message: Uncaught TypeError: Cannot set property 'value' of null at eval, which points at this line: source.value = destination.textContent;. It's not a big problem though, but still it's strange that it returns this mistake...

来源：https://stackoverflow.com/questions/52674962/copy-div-from-parent-website-to-a-textarea-in-iframe