Get element by tag (with obscure character)

Question

I could use a little help defining the method of getting a tag name when the tag name contains an obscure character.

artist=(x[i].getElementsByTagName("content:encoded")[0].childNodes[0].nodeValue);

I tried and failed with:

artist=(x[i].getElementsByTagName("content" + : + "encoded")[0].childNodes[0].nodeValue);

The full js currently here. i want to also get the contents of the <content:encoded> tag that is also present in every item.

$(document).ready(function() {


if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.open("GET","http://doobox.co.uk/rss/page1/files/blog.xml",false);
xmlhttp.send();
xmlDoc=xmlhttp.responseXML; 

x=xmlDoc.getElementsByTagName("item");

i=0;

$(document).ready(function() {
displayItem()
});



function displayItem()
{
artist=(x[i].getElementsByTagName("title")[0].childNodes[0].nodeValue);
title=(x[i].getElementsByTagName("category")[0].childNodes[0].nodeValue);
year=(x[i].getElementsByTagName("link")[0].childNodes[0].nodeValue);
txt="Artist: " + artist + "<br />Title: " + title + "<br />Year: "+ year;
document.getElementById("ShowLatestBlog").innerHTML=txt;
}


$('.back').click(function() {
  if (i<x.length-1)
  {
  i++;
  displayItem();
  }
});



$('.forward').click(function() {
if (i>0)
  {
  i--;
  displayItem();
  }
});



});

Answer 1

Assuming you are dealing with XML:

getElementsByTagNameNS('http://example.com/namespace/of/content', 'encoded');

See also: a reference to the DOM method

Answer 2

when trying to retreive the contents of the xml tag <content:encoded> i dont acctually look for the full tag name like that, Just "encoded" eg:

content=(x[i].getElementsByTagName("encoded")[0].childNodes[0].nodeValue);