Examining the Events Associated with Inserting, Updating, and Deleting:
Step 2: Prohibiting NULL UnitPrices
This step of the VIDEO TUTORIAL will show case on how to implement a business rule during the updating process using a GridView control on the web page. In this case, the business rule states that the UnitPrice field can NOT be null in the underlying database table. Therefore, in order to enforce this business rule during the update process, the user must be alerted with a friendly error or alert message indicating the business rule. This alerting of an end user is accomplished by inspecting the UnitPrice value in the GridView’s RowUpdating event handler and alerting the end user by making the warning message to be visible. In addition, the update process is also cancelled by setting the GridViewUpdateEventArgs’s Cancel attribute to false. For detailed information and source code for this step, please refer to the original article.