Why does appending a <script> to a dynamically created <iframe> seem to run the script in the parent page?
I'm attempting to create an <iframe> using JavaScript, then append a <script> element to that <iframe>, which I want to run in the context of the <iframe>d document.
Unfortunately, it seems I'm doing something wrong - my JavaScript appears to execute successfully, but the context of the <script> is the parent page, not the <iframe>d document. I also get a 301 Error in Firebug's "Net" tab when the browser requests iframe_test.js, though it then requests it again (not sure why?) successfully.
This is the code I'm using (live demo at http://onespot.wsj.com/static/iframe_test.html):
iframe_test.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title><iframe> test</title>
</head>
<body>
<div id="bucket"></div>
<script type="text/javascript" src="http://jqueryjs.googlecode.com/files/jquery-1.3.2.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
$('#bucket').append('<iframe id="test"></iframe>');
setTimeout(function() {
var iframe_body = $('#test').contents().find('body');
iframe_body.append('<scr' + 'ipt type="text/javascript" src="http://onespot.wsj.com/static/iframe_test.js"></scr' + 'ipt>');
}, 100);
});
</script>
</body>
</html>
iframe_test.js
$(function() {
var test = '<p>Shouldn\'t this be inside the <iframe>?</p>';
$('body').append(test);
});
One thing that seems unusual is that the the code in iframe_test.js even works; I haven't loaded jQuery in the <iframe> itself, only in the parent document. That seems like a clue to me, but I can't figure out what it means.
Any ideas, suggestions, etc. would be much appreciated!
Answer
Had the same problem, took me hours to find the solution. You just need to create the script's object using the iframe's document.
var myIframe = document.getElementById("myIframeId");
var script = myIframe.contentWindow.document.createElement("script");
script.type = "text/javascript";
script.src = src;
myIframe.contentWindow.document.body.appendChild(script);
Works like a charm!