What is the view state of ASP.NET?

What is the view state of ASP.NET?

Rating:

ASP.NET uses a technique known as the view state. This technique is used to persist changes to the state of a Web page across postbacks. ASP.NET that manages a nonpostback Web server control such as Label control does not post its values as part of the postback operation to the Web server. ASP.NET collects all the values of the nonpostback control, formats them into an encoded string and stores in a hidden input field on a Web page. By default, the view state of a Web page is placed in a hidden form field named _VIEWSTATE.

At the server-side, ASP.NET decodes the view state string during page initialization and restores the nonpostback values in the Web page. But this view state technique increases the size of the HTML file and the amount of time to load the page. To eliminate these drawbacks, ASP.NET provides a disabling feature that does not enable view state at various levels, which are as follows:

• Control Level: To populate a control's state at each request, the view state can be disabled at the control level by setting the EnableViewState property of the control to false. For example, <asp: ListView EnableViewState="False" />.



• Page Level: At the page level, setting the EnableViewState attribute of the @ Page directive to false can disable view state. For example, <%@ Page EnableViewstate="False" %>.


• Application or Machine Level: View state can also be disabled by adding <pages enableViewState="false" /> to a Web.config file at the application level or to a Machine.config file at the machine level.

Rating: