Message Contract in WCF

Question

I have learn about WCF and its different contracts, When I came to know about Message Contract, I am not understand what is use of Message Contract when we have data contract?

Plz reply with best answer....

Santhosh Kumar Jayaraman · Answer

Data contracts are used to define the data structure. Messages that are simply a .NET type lets say in form of POCO (plain old CLR object) and generate the XML for the data you want to pass. Message contracts are preferred only when there is a need to control the layout of your message(the SOAP message); for instance adding specific headers/footer/etc to a message. Sometimes complete control over the structure of a SOAP message is just as important as control over its contents. This is especially true when interoperability is important or to specifically control security issues at the level of the message or message part. In these cases you can create a message contract that enables you to use a type for a parameter or return value that serializes directly into the precise SOAP message that you need.