Reading and Storing Data in ViewState

The ViewState collection provides an easy way to maintain values on a particular Web

Form across postbacks.This collection is stored as a hidden form field, and thus all data

stored in ViewState is passed to and from the client on every request.You access it using

syntax similar to what you have seen for the Session and Application collections:

ViewState("UserName")="UserNameTextBox.Text"

UserNameLabel.Text = ViewState("UserName")

Comments

By default,Web controls that do not post back values will maintain their state automatically

using ViewState.This can be controlled individually for each control or globally for

each page by setting

EnableViewState to true or false as desired (either for a given

control or in the page directive).The amount of space a control occupies in ViewState

can easily be determined from the control tree section of the trace output.