XMLHttpRequest. Permission denied to call method XMLHttpRequest.open

	XMLHttpRequest Webneurons Web 3 \| XML

Webneurons Web 3 Home

Back
Page titles A-Z index

Main Pages

Original Posting
Original Site
Newsgroup Post
Web 3
Wrong Approach
XML

Reference

XML - XMLHttpRequest, Minimal javascript xml parser, and the Ajax system of xmlHttpRequest, DOM and style sheets, for adjusting web pages without reloading.

XMLHttpRequest. Permission denied to call method XMLHttpRequest.open

The below script should work if pasted into a local page i.e. a file://... url and you are connected to the internet. That should be all you need to do. It should fill out the items box when you select a category. The script has also been put into column 3 of this page.

If you put the script online then you need to make requestFol (below) the same as the folder url where you put the script. Also copy over the 4 xml files http://www.webneurons.com/songs.xml, albums.xml, newreleases.xml, and justadded.xml.

This is the line to be changed:-
requestFol = "http://www.webneurons.com/"
in function loadDoc(xmlFile)

XMLHttpRequest will not apparently work for Mozilla browsers if the online request folder is on a different server from the online script folder.

If you try it you should get an error:-

"Permission denied to call method XMLHttpRequest.open"

It seems that security worries have killed ease of use since there could be many applications where a single html page would want to display many different text boxes with http requests coming from various different servers.

One way round this is for the script server to pull the information from all the request servers and send to the single client page but this means programming in php or something similar.

The "Cycle" button should behave as if you selected each of the 4 categories one after the other. After running it once you have to clear your browser cache/temporary internet files, otherwise it will use the local cache and not request the server.

XMLHttpRequest Object Demo

Dynamic HTML and XML: The XMLHttpRequest Object - developer.apple.com

// global request and XML document objects
var req;

function appendToSelect(select, value, content) {
// add item to select element the less
// elegant, but compatible way.
    var opt;
    opt = document.createElement("option");
    opt.value = value;
    opt.appendChild(content);
    select.appendChild(opt);
}

function clearTopicList() { // Called from processReqChange() when the xml file is received
// empty Topics select list content
    var select = document.getElementById("topics");
    while (select.length > 0) {
        select.remove(0);
    }
}

function selectCycle(i) {
// i_g used in processReqChange() above
i_g=i+1
loadDoc(document.xml_test.categories.options[i].value)
}

</script>

<h3>XMLHttpRequest Object Demo</h3>
<form name="xml_test">
<input type="button" value="Cycle" onClick="selectCycle(1)"><BR><BR>
<p>Category:<br />
<select name="categories" onchange="selected(event)">
    <option value="">Choose One</option>
    <option value="songs.xml">Top 10 Songs</option>
    <option value="albums.xml">Top 10 Albums</option>
    <option value="newreleases.xml">Top 10 New Releases</option>
    <option value="justadded.xml">Top 10 Just Added</option>
</select>
</p>
<p>Items:<br />
<select size="15" id="topics" onchange="showDetail(event)">
    <option value="">Choose a Category First</option>
</select>
</p>
</form>
<div id="details"><span></span></div>