1.You should create a Library Project (DLL) that must not depend on any other project from your specific application, then put into it the reusable code.
Then share this utility project in all your applications by adding, in each application solution, this existing project (by using Add Existing Project from Solution Explorer).
2.If you do not want a real library, other solution could be to create project templates (that have some basic common parts already implemented) then to use them for creating similar applications. For details about this see in
MSDN.[
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