Difference between ViewState and SessionState?
Difference between ViewState and SessionState
Before diving into the difference between ViewState and Session State, it’s necessary to understand what state management is.
State Management
A strategy for controlling the state is state management. The management of the state becomes more difficult as an application grows. It is known that the web is stateless, which means every time a specific webpage is requested. It is recreated each time and posted to the server. Also, HTTP is a stateless protocol, i.e. it cannot hold client information on the webpage. So it need to maintain the state of a page and the server-side as well, State management is done.
ViewState and SessionState are used for client-side state management and server-side state management respectively. The basic difference between these two is that the ViewState is to manage state at the client’s end, making state management easy for end-user while SessionState manages state at the server’s end, making it easy to manage content from this end too.
What is ViewState?
Viewstate is a client-side mechanism for managing state. Viewstate is a specific type of data that only applies to the page where it is utilised.
It saves the data on the same page in encrypted format. Information that you want to access from the same web page is stored in ViewState. ViewState of one page cannot be accessed directly from another page. If you want to access a specific ViewState value, you can store it in the Context collection and then access it from another page.
Key points of Viewstate:
- Only page level maintenance.
- Only one page, not several pages, can display the view state.
- When a new page is loaded, ViewState values are lost or cleared.
What is Session State?
Session State is a method for managing server-side state. When a new client first interacts with a Web application, a session ID is generated and associated with all subsequent requests from the same client for the duration of the session. It is used mainly for storing user specific data [session specific data]. The session value can be used for the whole session until the session expires or the user closes the session. The session value in accessible on all the pages.
When it comes to storing data on a browser, session storage is a popular option. It allows developers to save and retrieve various values. Session storage, as opposed to local storage, only keeps data for a single session. When the user closes the browser window, the data is cleared.
The SessionState will be cleared if the following conditions are met:
- Cleared by the programmer
- Cleared by the user
- Cleared when Timeout occurs
