title: Access to cpp file in another project in Visual Studio 2019
body: <p>I have two C++projects(Visual Studio Community Edition 2019) called Game(e) and Tester in a solution map. Tester is a subdirectory of Game. Both projects creates exe files.
  The projects Game hast two cpp and two header files(Foo.cpp, Foo.h, Foo2.cpp and Foo2.h).</p>
  <p>Foo has two methods add1 and add2. Foo2 has the method plus_one. The method add2 from Foo uses plus_one.
  In the project Tester there is a file called Main.cpp. I want to use all the files from Gamer in the project Tester. I have added &quot;..&quot; to &quot;Additional Include Directories&quot; so that I can include Foo.h in Tester\Main.cpp. I have added a reference to Games. The problem is that the linker doesn't like it:</p>
  <pre><code>Error   LNK2019 unresolved external symbol &quot;public: int __thiscall Foo::add(int,int)&quot; (?add@Foo@@QAEHHH@Z) referenced in function _main
  Error   LNK2019 unresolved external symbol &quot;public: int __thiscall Foo::add2(int,int)&quot; (?add@Foo@@QAEHHH@Z) referenced in function _main
  </code></pre>
  <p>Does anybody know how to fix it? One solution is to import both cpp-files into the Tester project. But this solution is not acceptable for me. I am interested in a solution without importing all cpp files. I have uploaded it on github: <a href="https://github.com/tellass567/game" rel="nofollow noreferrer">Github Link</a></p>