The
As with any other Web server control, the information in a HiddenField control is available during postback. The information is not persisted outside the page.
HiddenField Control and Security
The information in a HiddenField control is not displayed when the browser renders the page, but users can see the contents of the control by viewing the page's source. Therefore, do not store sensitive information in a HiddenField control, such as user IDs, passwords, or credit card information.
Detecting Changed Data
Users can change the value of a HiddenField control before the page is posted back to the server, potentially compromising the information. To help you detect this type of change, the HiddenField control raises a