javascript location.hash refreshing in IE

Question

I need to modify the hash, remove it after certain processing takes place so that if the user refreshes they do not cause the process to run again.

This works fine

Answer 1

This appears to be a bug with Internet Explorer (tested with 7 and 8).

Changing window.location.hash should not result in a reload, and it is a common JavaScript technique to use the hash for maintaining state.

If you manually load a page and change the hash using JavaScript it will work.

The problem is when you are redirected to the page from a different location (ie: using HTTP header "Location"), then modifying the hash will result in a reload.

To get around this bug you could:

1) If you can control the redirect, you could replace the Location header with some HTML.

2) if not, you could try reloading the page when it is loaded. To prevent a reload loop you may need to set a cookie.

window.location = window.location; // window.location.reload() didn't work.

In pseudo code: 

// if is Internet Explorer
//      if ( cookie "reloadPerformed" is not set )
//          set cookie "reloadPerformed" = "1"
//          reload page
//      else 
//          clear cookie "reloadPerformed"

The obviously drawback is that loading the page results in two page request & render, so you'll would want the reload to be one of the first things the page does when it loads.