IsPostBack Boolean property can be used to execute code only when the page is first loaded, not every time the page is submitted. Initially, when the page is first loaded, the value of this property is false. When the page is submitted, the value of this property becomes true. This technique has two advantages:
• It conserves system resources and enables the page to be re-loaded faster. Retrieving records from the database and affects the performance of the page.
• It maintains the user’s selection with the help of the list control’s properties, SelectedIndex, and SelectedItem.