Google allows external applications to access their search engine through their search webservice. This webservice, and many others, was implemented via the Simple Object Access Protocol, or SOAP. SOAP is a ‘lightweight’ protocol that is ideal for exchanging information in web environments, since it provides a standard way for passing data between different types of systems. It is based on XML, and allows for the definition of simple objects and Remote Procedure Calls, or RPC (calling a method from your program that ‘lives’ on another server) and the RPC responses.
In order to take advantage of this web service using ASP.NET, we’re going to have to build a proxy class which will serve as an intermediary between our program and the web service. That sounds like a whole lot of work, but fear not, Microsoft has a utility (wsdl.exe) that automates this process for us.
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