How do I correctly reference to code in a different project in C#?

In short: I have a console application with a static Dictionaries, which work fine in the project they were written in. How do I reference to this project correctly, so that I can do the same from a different project? I get an error every time I try to call the function to load the data into them.

Long story: For a school project I'm making a scheduler for a garbage collection company using local search algorithms. I have everything in a console app (project name: LocalSearch), but I wanted to make a visualiser, so I can better analyse the solutions it produces. I am using a Windows Forms Application (project name: ScheduleVisualiser) for this purpose and I wanted to reference to the console app so I don't have to load the data again.

In the console app I have all my data loading done in the Program class. I have the following code:

public static Dictionary<int, Order> Orders = new Dictionary<int, Order>();

public static void Main()
{
    LoadData();
    ...
}

public static void LoadData()
{
    ...
}

Now I have my WFA and I have added console app as a reference, but when I do LocalSearch.Program.LoadData(), Visual Studio goes into break mode and it throws the following expection:

System.IO.FileNotFoundException HResult=0x80070002 Message=Could not load file or assembly 'System.Runtime, Version=4.2.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified. Source= StackTrace:

What am I doing wrong?

You cannot use the Console application as a Library. You either have to convert it to a library type project or run as a ".exe" with proper parameters.

So technically there are 3 options:

1. If you don't need a Console app anymore - simply change the Project type to Class Library:

Right-click Project -> Properties -> Application -> Output Type: 'Class Library'

2. If you still need your Console app and want to share the same logic between the Console and WinForms - Move all your logic to the Class Library and use both in Console and WinForms.

3. If you need just input/output data from the Console Application - you can run it as an external application (but it is the worst scenario)

       using (Process process = new Process())
       {
           process.StartInfo.FileName = "ipconfig.exe";
           process.StartInfo.UseShellExecute = false;
           process.StartInfo.RedirectStandardOutput = true;
           process.Start();
   
           // Synchronously read the standard output of the spawned process.
           StreamReader reader = process.StandardOutput;
           string output = reader.ReadToEnd();
   
           // Write the redirected output to this application's window.
           Console.WriteLine(output);
   
           process.WaitForExit();
       }