AJAX Question

Question

Lee-Pro 0 Newbie Poster

16 Years Ago

Hey everyone, this is a very tough problem I am facing right now in JavaScript.

I'm designing this script to load a page like an IFrame but is using AJAX, the only problem is that I need to edit certain attributes before displaying them through changing an element's innerHTML attribute.

Using the normal xmlHttp request, it retrieves a html document. But is there any way I could actually handle it through some kind of DOM before actually displaying it?

Modifying them after I display them is troublesome as the browser would convert relative links into absolute paths.

Using XML to load the document was fine, but then there was no way to generate the HTML code without lots of hassle.

Is there any other way?

PS: An older version of script is in my site, but it uses substr which is very messy.

javascript

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Latest Post 16 Years Ago Latest Post by Lee-Pro

digital-ether 399 Nearly a Posting Virtuoso

16 Years Ago

Hey everyone, this is a very tough problem I am facing right now in JavaScript.
I'm designing this script to load a page like an IFrame but is using AJAX, the only problem is that I need to edit certain attributes before displaying them through changing an element's innerHTML attribute.
Using the normal xmlHttp request, it retrieves a html document. But is there any way I could actually handle it through some kind of DOM before actually displaying it?
Modifying them after I display them is troublesome as the browser would convert relative links into absolute paths.
Using XML to load the document was fine, but then there was no way to generate the HTML code without lots of hassle.
Is there any other way?
PS: An older version of script is in my site, but it uses substr which is very messy.

You could load the HTML with an XML content-type so that you can access the response as XML (XMLHttpRequest.responseXML).
Traverse each node in the XML Doc and create equivalent DOM nodes in your HTML Document.

Example:

/**
* Clones XML nodes to the current Document's DOM
*/
function cloneXMLtoDOM(Node) {
	var DOMNode;
	if (Node.nodeName == '#text') {
		// clone text nodes
		DOMNode = document.createTextNode(Node.data);
	} else {
		// clone root node
		DOMNode = document.createElement(Node.nodeName);
		// clone the attributes
		for(var i = 0; i < Node.attributes.length; i++) {
			DOMnode.setAttribute(Node.attributes[i].nodeName, Node.attributes[i]);
		}
		// recursively clone the child nodes
		if (Node.hasChildNodes()) {	
			for(var i = 0; i < Node.childNodes.length; i++) {
				DOMNode.appendChild(cloneXMLtoDOM(Node.childNodes[i]));
			}
		}
	}
	return DOMNode;
}

You could also use XPATH which would be faster.

~s.o.s~ 2,560 Failure as a human

16 Years Ago

> Using the normal xmlHttp request, it retrieves a html document. But is there any way I could
> actually handle it through some kind of DOM before actually displaying it?
Make sure that the page you fetch using XHR is well formed. If that is the case, you can manipulate the contents of the response just as you would to a normal HTML document.

var doc = xmlHttpRequest.responseXML;
doc.getElementsByTagName("someTag")[0].someAttribute = someValue;

> DOMnode.setAttribute(Node.attributes[i].nodeName, Node.attributes[i]); IE doesn't like set/getAttribute . Use obj.attribute = value; for maximum browser compatibility.

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Lee-Pro 0 Newbie Poster · Answer 1 · 2008-01-24T17:17:31+00:00

Hey, thanks for the XMLtoDom converter, but when I tried using it I got this:

Error: [Exception... "String contains an invalid character"  code: "5" nsresult: "0x80530005 (NS_ERROR_DOM_INVALID_CHARACTER_ERR)"  location: "file:///home/leezh/test.html Line: 57"]
Source File: file:///home/leezh/test.html
Line: 57

The source is here:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
</head>
<body>

<script type="text/javascript">
var xmlHttp;
try
{
  // Firefox, Opera 8.0+, Safari
  xmlHttp=new XMLHttpRequest();
}
catch (e)
{
  // Internet Explorer
  try
  {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
  }
  catch (e)
  {
    try
    {
      xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
    catch (e)
    {
      alert("Your browser does not support AJAX!");
    }
  }
}

xmlHttp.onreadystatechange=function()
{
  if(xmlHttp.readyState==4)
  {
    var doc = xmlHttp.responseXML;
    // Some XML DOM stuff
    document.getElementsByTagName("body").appendChild(cloneXMLtoDOM(doc));
  }
}
xmlHttp.open("GET","books.xml",true);
xmlHttp.send(null);

/**
* Clones XML nodes to the current Document's DOM
*/
function cloneXMLtoDOM(Node) {
	var DOMNode;
	if (Node.nodeName == '#text') {
		// clone text nodes
		DOMNode = document.createTextNode(Node.data);
	} else {
		// clone root node
		DOMNode = document.createElement(Node.nodeName);
		// clone the attributes
		for(var i = 0; i < Node.attributes.length; i++) {
			DOMnode.setAttribute(Node.attributes[i].nodeName, Node.attributes[i]);
		}
		// recursively clone the child nodes
		if (Node.hasChildNodes()) {	
			for(var i = 0; i < Node.childNodes.length; i++) {
				DOMNode.appendChild(cloneXMLtoDOM(Node.childNodes[i]));
			}
		}
	}
	return DOMNode;
}
</script>

</body>
</html>

Is anything wrong?

digital-ether 399 Nearly a Posting Virtuoso Team Colleague · Answer 2 · 2008-01-24T22:47:41+00:00

digital-ether 399 Nearly a Posting Virtuoso

16 Years Ago

Could you post the XML response from the server.

digital-ether 399 Nearly a Posting Virtuoso Team Colleague · Answer 3 · 2008-01-25T02:04:00+00:00

There was a problem in the function cloneXMLtoDOM's cloning of attributes. Here's it again, fixed:

/**
* Clones XML nodes to the current Document's DOM
*/
function cloneXMLtoDOM(Node) {
	var DOMNode;
	
	if (!Node) return false;
	
	if (Node.nodeName == '#text') {
		// clone text nodes
		DOMNode = document.createTextNode(Node.nodeValue);
	} else {
		// clone root node
		DOMNode = document.createElement(Node.nodeName);
		// clone the attributes
		for(var i = 0; i < Node.attributes.length; i++) {
			DOMNode.setAttribute(Node.attributes[i].nodeName, Node.attributes[i].nodeValue);
		}
		// recursively clone the child nodes
		if (Node.hasChildNodes()) {	
			for(var i = 0; i < Node.childNodes.length; i++) {
				DOMNode.appendChild(cloneXMLtoDOM(Node.childNodes[i]));
			}
		}
	}
	return DOMNode;
}

If it doesn't work for you, just use the DOM methods on the responseXML to make modifications and append it to the document using innerHTML like s.o.s mentioned

Lee-Pro 0 Newbie Poster · Answer 4 · 2008-01-28T16:12:35+00:00

Hey, guys, I found this solution to the problem while searching about:

http://www.captain.at/howto-javascript-convert-string-to-xml-to-string.php

The problem was so simple with just one line of code needed:

var string = (new XMLSerializer()).serializeToString(xmlobject);

But thanks for the help anyways.