Restoring Lost Focus in the Update Panel with Auto Post-Back Controls

UpdatePanel control is used for different purposes like reducing flickering of the page and reducing network traffic generated by a web site. Developers often wrap input boxes into an UpdatePanel to implement cascading drop-downs and update other related controls. Cascading drop-downs can be implemented with a help of Ajax Control Toolkit control extenders, but in general case you will either need to write script code or place controls in an update panel. The latest approach is very easy to implement, but it also has a lot of drawbacks. If you wrap input boxes (and other input controls) in the update panel, you must be aware about the following consequences: