View Full Version : DHTML Window Caching problem

06-25-2005, 01:24 AM
dhtml window


I'm having a bit of an issue with the DHTML window routine. I am using the DHTML window to display a local page when the user selects a link on the main page. If I change the page being displayed in the iframe, the page displayed in the DHTML window does not change. The only way I can update it is to load the iframe src page in a regular window and refresh it. Then, when I show the page in the DHTML window, it will show the updated page.

Is there any way to initialize the script so that when the user selects refresh, the cache is cleared of the old page so the new version is loaded?



06-25-2005, 03:09 AM
I'm not very clear on what you are saying. I had a demo of this script set up already. I removed this part:
//Use below code to load DHTML Window as page loads
if (ns6) window.onload=new Function('loadwindow("http://www.google.com",600,400)')
</script>Then I added to the existing link that comes with the script so that I had these two links:
<a href="javascript:loadwindow('http://www.google.com',600,400)">Geocities</a><br>
<a href="javascript:loadwindow('http://www.yahoo.com',600,400)">Yahoo</a>Now, when the page loads, also when it is refreshed, there is no pop-up visible. If I click on either link, I get the pop-up with the appropriate page in it. If I click on the other link, while the first is visible, the second replaces it, if I close the pop-up, it goes away. If I refresh, the pop-up goes away. Anyways, what do you expect to have happen?

06-29-2005, 02:04 AM
I was talking about publishing changes to the website.

Let's say I have a DHTML window in index.html pointing to say About.html.

In a browser I am showing http://www.mysite.com/index.html

I make a change to About.html and publish it to the site.

When I refresh index.html, it still shows the old version of About.html in the DHTML window. In order to refresh the DHTML window, I have to open http://www.mysite.com/About.html, then, when I go back to index.html it shows the new About.html in the DHTML window.

So far it's not such a bad problem, I guess I'm just worried about showing dynamically changing pages in DHTML windows, perhaps it won't update appropriately in certain situations.


06-29-2005, 03:20 AM
I was playing around with this DHTML window script some more and have decided it isn't one of my top picks for reliability. The biggest problem is that the drag and drop feature in IE is shaky and no amount of tweaking I have come up with so far makes it 100%. I see you have disabled the drag and drop feature in your implementation - good idea. Another thing I discovered was that using this syntax to launch content in the iframe:
<a href="javascript:loadwindow('Win_About.htm',550,760)">About</a>isn't the best way to go about it. It causes some minor problems in Mozilla and will cause an error if javascript is disabled. A better approach is:
<a href="Win_About.htm" onclick="loadwindow(this.href,550,760);return false;">About</a>That way, non javascript enabled browsers will be taken to the page itself and Mozilla won't be tempted to endlessly spin its little 'loading . . . ' symbol.

As far as pages getting cached. Generally that happens when the page is in your history and you are accessing it via the same link from the same page you did last time. Some servers are better at avoiding this than others. Your browser can be configured to always check for updated content. You can clear your cache frequently or set it to clear each time the browser is closed. There are also meta tags that can be placed on a page to prevent it from being loaded without checking to see if it has been updated:

<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Expires" content="Mon, 01 Jan 1990 12:00:00 GMT">
<meta http-equiv="Cache-control" content="no-cache">
<meta http-equiv="Cache-control" content="must-revalidate">
<meta http-equiv="Cache-control" content="max-age=0">These go in the head of the document. They are no guarantee but, work in most cases.