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How to detect and prevent new browser instance

Posted By:      Posted Date: August 25, 2010    Points: 0   Category :ASP.Net

Hi Folks,

I have a problem w/ a web app which is probably fairly common, but I cannot find any solutions anywhere. Hopefully someone will have an idea.

The web app in question provides a UI for editing a client (in the business sense, not the browser sense), identified by a ClientID.  I store the ClientID in Session, which gets passed from page to page, along with a number of other pieces of data in Session.  Works great.

The problem is that if the user opens a new browser window using Ctrl N or File->New Window (in IE), the new window comes up with the same page as the current page, with the same session info. Then if the user navigates to a different client in the 2nd window, the ClientID in session refers to the new client. If they go back to the original browser window and save, the original client gets saved using the 2nd ClientID, and all hell breaks loose, because now the data from the two jobs are intertwined.

I have enabled trace and verified that the new browser window uses the same SessionID as the original.  If an entirely new instance of IE is opened, it has a different SessionID, so is not a problem.  I have not yet investigated other browsers, such as Chrome or Firefox.

Is there any way to determine if a browser instance is opened for a web app which is already open in

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