how can I use google search engine to Search my source code for "Copy pasted code snippet" from web

I am planning to develop an application which would search my source code for copy pasted "code snippet" from web

As an initial step say I want to search only Function signature

(Motivation Behind: Copy pasting code might lead to Licensing issues)

Q1. Where should I start?..开发者_开发百科...How can I use google search engine to achieve my goal ?

Q2. Is it possible to develop standalone windows app or I have to go for ASP.net?