Javascript XML序列化（IE问题）

Question

I use the following code to generate XML, see codepen

var doc = document.implementation.createDocument ('http://www.w3.org/1999/xhtml', 'root', null);

var somenamespace = "http://somenamespace.com/schema";
doc.documentElement.setAttributeNS('http://www.w3.org/2000/xmlns/', 'xmlns:' + "pref", somenamespace);

var el1 = doc.createElementNS(doc.documentElement.namespaceURI, "el1");
doc.documentElement.appendChild(el1);

var el2 = doc.createElementNS(doc.documentElement.namespaceURI, "el2");
el1.appendChild(el2);

el2.setAttributeNS(somenamespace, "pref" + ":" + "foo", "bar");

var serializer = new XMLSerializer();
var raw = serializer.serializeToString(doc);
document.body.innerText = raw;

It works as expected in Chrome, Firefox, Safari, but IE drops my xmlns:prefix where I set it and writes in other XML nodes.

Expected:

<root
    xmlns="http://www.w3.org/1999/xhtml"
    xmlns:pref="http://somenamespace.com/schema">
    <el1>
        <el2 pref:foo="bar"></el2>
    </el1>
</root>

IE:

<root
 xmlns="http://www.w3.org/1999/xhtml">
 <el1>
  <el2
   xmlns:pref="http://somenamespace.com/schema" pref:foo="bar">
  </el2>
 </el1>
</root>

What can I do to workaround and make IE write xmlns in the root element (where I set it)?

Answer 1

What can I do to workaround and make IE write xmlns in the root element (where I set it)?

Nothing.

Your expected and actual XML are fully equivalent. No compliant XML processor will treat the two forms differently. You should not care either.