I'm not sure I understand your question. I know what a cookie is, but I'm not sure what a "session value" is to you. Is this some piece of data that is stored in your server? Is it stored in the URL? Is it stored in the browser somehow (in a cookie)?
I'm going to assume it is a piece of data stored by the application running on the server. There is kind of a brick wall between the framework and what is running on the web server. We can only access the DOM from the browser and the cookies for it. We cannot directly access anything contained on the server.
If you can come up with some mechanism to access this server data and present it in the browser, such as a special URL that fetches reads and returns this session data in the browser then we'll be able to access it.
Beyond that I need clarification on what/where this session value is so we can assist you with how to access and validate it.
the Telerik team
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