what is the use of WSDL?

Sir/Madam, I want to know where WSDL exists. Do user need to do inte开发者_运维百科ract with it for any kind of scenario during programing?

WSDL (Web Services Description Language) is an XML-based language for describing Web services and how to access them.

Web Services Description Language

With respect, this is a bad question. You're in effect asking us to do your research for you. When I say "bad" what I mean here is that you're in danger of harming yourself by asking questions like this. If instead you do some preliminary research, for example by googling WSDL, and find resources such as this then you expose yourself to the "Encyclopedia Effect", you encounter other related (or indeed unrelated information) and you learn more. When you research and come across something you don't understand then you can ask specific questions in places like this, and you have a context to understand the answers. I truly believe that researching in the way I describe will be most helpful to you in the long term.

To give one answer to your questions: you will find examples of useful WSDLs here.

As a programmer you can develop service clients from those WSDLs, or more usually use code generators to write the "boilerplate" code for you.

If you want to provide your own services then you may write WSDLs your self.

WSDL stands for Web Service Description Language, it uses XML to define functions that a web service exposes and the types that these functions receive as arguments and return.

http://en.wikipedia.org/wiki/WSDL

You can usually access the WSDL for a web service using a query string (in .NET web services at least). A developer usually won't look at the WSDL as it will be generated by a tool like Visual Studio or soapsuds and code will be generated to represent the types based on the definition in the WSDL that the developer will make use of instead. Changes to the WSDL will result in regeneration of this code.