I have seen there are lots of myth’s about asp.net web services in fresher level asp.net developers. So I decided to write a blog post about asp.net web services interview questions. Because I think this is the best way to reach fresher asp.net developers. Followings are few questions about asp.net web services.
1) What is asp.net web services?
Ans: Web services are used to support http requests that formatted using xml,http and SOAP syntax. They interact with through standards xml messages through Soap. They are used to support interoperability. It has .asmx extension and .NET framework contains http handlers for web services to support http requested directly.
2) What kind of data can be returned web services web methods?
Ans: It supports all the primitive data types and custom data types that can be encoded and serialized by xml. You can find more information about that from the following link.
http://msdn.microsoft.com/en-us/library/bb552900.aspx
3) Is web services are only written in asp.net?
Ans: No, It can be written by Java and PHP languages also.
4) Explain web method attributes in web services
Ans: Web method attributes are added to a public class method to indicate that this method is exposed as a part of XML web services. You can have multiple web methods in a class. But it should be having public attributes as it will be exposed as xml web service part. You can find more information about web method attributes from following link.
http://msdn.microsoft.com/en-us/library/byxd99hx(v=vs.71).aspx
5) What is SOA?
Ans: SOA stands for “Services Oriented Architecture”. It is kind of service oriented architecture used to support different kind of computing platforms and applications. Web services in asp.net are one of the technologies that supports that kind of architecture. You can call asp.net web services from any computing platforms and applications.
6) What is SOAP,WDSL and UDDI?
Ans: SOAP stands “Simple Object Access protocol”. Web services will be interact with SOAP messages written in XML. SOAP is sometimes referred as “data wrapper” or “data envelope”.Its contains different xml tag that creates a whole SOAP message. WSDL stand for “Web services Description Language”. It is an xml document which is written according to standard specified by W3c. It is a kind of manual or document that describes how we can use and consume web service. Web services development software processes the WSDL document and generates SOAP messages that are needed for specific web service. UDDI stand for “Universal Discovery, Description and Integration”. Its is used for web services registries. You can find addresses of web services from UDDI.