Explain View State? And its advantages and disadvantages.

Answer

Suppose a user submits a form and there are validation errors or if the page refreshes after the user enters a lot of information on the page. In such cases, the information already written by the user will be lost, and he/she has to fill everything again. To avoid this from happening, ASP.NET uses ViewState, which retains the values already entered by the user. It is a built-in state management technique to preserve the form data. 

Advantages:

• Ensures security as data is stored in an encrypted format.
• No server resources used.
• ViewState properties can be easily enabled or disabled.
• Developers can develop it at page level or control level as per need.

Disadvantages:

• If a huge amount of data is stored, loading the page may take longer than required.
• Data doesn't transfer from one page to another (between pages).