Final answer:
To access data stored in the ViewState variable of one page from another page, you can use cross-page posting or session state in ASP.NET.
Step-by-step explanation:
To access the data stored in the ViewState variable of one page from another page in ASP.NET, you can use cross-page posting or session state.
In cross-page posting, you can set the PostBackUrl property of a Button control to the URL of the target page. On the target page, you can access the ViewState variable using the Page.PreviousPage property and its FindControl method.
Alternatively, you can store the data in the session state using the Session object and retrieve it on the target page using the Session object again.