Interview Questions

Asp.Net Back

Explain what a diffgram is, and a good use for one?

Ans:  A DiffGram is an XML format that is used to identify current and original versions of data elements. The DataSet uses the DiffGram format to load and persist its contents, and to serialize its contents for transport across a network connection.

Describe the difference between inline and code behind - which is best in a loosely coupled solution?

Ans:  ASP.NET supports two modes of page development: Page logic code that is written inside "script runat=server" blocks within an .aspx file and dynamically compiled the first time the page is requested on the server. Page logic code that is written within an external class that is compiled prior to deployment on a server and linked "behind" the .aspx file at run time.

What's an assembly?

Ans:  Assemblies are the building blocks of .NET Framework applications; they form the fundamental unit of deployment, version control, reuse, activation scoping, and security permissions. An assembly is a collection of types and resources that are built to work together and form a logical unit of functionality.

Can you explain what inheritance is and an example of when you might use it?

Ans:  Inheritance is a fundamental feature of an object oriented system and it is simply the ability to inherit data and functionality from a parent object. Rather than developing new objects from scratch, new code can be based on the work of other programmers, adding only new features that are needed.

Explain the differences between Server-side and Client-side code?

Ans:  Server side scripting means that all the script will be executed by the server and interpreted as needed. ASP doesn't have some of the functionality like sockets, uploading, etc. For these you have to make a custom component usually in VB or VC++. Client side scripting means that the script will be executed immediately in the browser such as form field validation, clock, email validation, etc.

What's the difference between authentication and authorization?

Ans:  Authentication happens first. You verify user's identity based on credentials. Authorization is making sure the user only gets access to the resources he has credentials for.

What's a code group?

Ans:  A code group is a set of assemblies that share a security context.

None, Windows, Forms and Passport..

Ans:  The CLR computes actual permissions at runtime based on code group membership and the calling chain of the code.

What are the authentication modes in ASP.NET?

Ans:  None, Windows, Forms and Passport.

What is delay signing?

Ans:  Delay signing allows you to place a shared assembly in the GAC by signing the assembly with just the public key. This allows the assembly to be signed with the private key at a later stage, when the development process is complete and the component or assembly is ready to be deployed. This process enables developers to work with shared assemblies as if they were strongly named.