That really is a very silly mistake

If you are working with MVC framework, why dont you try out Ajax instead of update panels. Thats a much better option

An interface defines the signatures for a set of members that implementers must provide. Interfaces cannot provide implementation details for the members. For example, the ICollection interface defines members related to working with collections. Every class that implements the interface must supply the implementation details for these members. Classes can implement multiple interfaces. Classes define both member signatures and implementation details for each member. Abstract classes can behave like interfaces or regular classes in that they can define members, and they can provide implementation details but are not required to do so. If an abstract class does not provide implementation details, concrete classes that inherit from the abstract class are required to provide the implementation. So here you can see the difference. Based on the understanding about your requirements in the project. You should implement either Interface of abstract class.

Try to achieve your functionality with JavaScript/Jquery

The "Default" route map should always be placed at the end. Try swapping the two MapRoute and it will work.

In order to call the JavaScript function, Just use the Following: protected void Page_Load(object sender, EventArgs e) { TextBox1.Attributes.Add("onfocus", "Open()"); } This will bind the "onfocus" event of TextBox1 to the javascript function "Open()"