JavaScript: How do I change the Hash in the Address Bar WITHOUT adding an entry to history?

Question

I'm trying to expand on an idea from someone else's question, and running into difficulty.

The idea is to insert the utm_source (from an ad campaign) into the url hash dynamically, have Google Analytics track the page, and then remove the hash. (We don't want to keep the hash because: 1. it's a duplicate page, and 2. If the user bookmarks it and comes back, it looks like another ad click)

Here's the code that almost works:

// save the old hash
var campaignSource = "Some Banner Ad";
var oldHash = document.location.hash;

// add campaign data to the hash
document.location.hash = 'utm_source=' + escape(campaignSource);
pageTracker._setAllowAnchor(true);
pageTracker._trackPageview();
// restore the old hash:
document.location.hash = oldHash;

The caveat is that it adds two more entries to the history (back button) on each change.

The question: How can I make the browser skip the history for hash changes?

Answer 1

You can leave the second hash change out and just use

history.back();

to go back one step. This results in no new pages in back button but one page on forward button which will disappear when the user navigates to somewhere else.

I don't think you can prevent the hash change sticking into the history.

Answer 2

If you want to skip adding the entry to the history, then use window.location.replace instead

window.location.replace("#hash");

This way the URL on the address bar will be replaced instead of adding a new entry to the browser history object