C# importing class into another class doesn't work

Question

I'm quite new to C#, and have made a class that I would like to use in my main class. These two classes are in different files, but when I try to import one into the other with using, cmd says says

The type or namespace name "MyClass" could not be found (are you missing a using directive or an assembly reference?

I know that in Java I have to mess around with CLASSPATH to get things like this to work, but I have no idea about C#.

Additional details:

As you've probably figured out, I'm compiling and executing via command prompt. I'm compiling my non-main class using /target:library (I heard that only main classes should be .exe-files).

My code looks like this:

public class MyClass {     void stuff() {      } } 

and my main class:

using System; using MyClass;  public class MyMainClass {     static void Main() {         MyClass test = new MyClass();         /* Doesn't work */     } } 

I have tried to encompass my non-main class with namespace MyNamespace { } and importing that, but it doesn't work either.

Answer 1

UPDATE: As of C# 6, if you want to use the static members of a class without specifying the class name, you can use the using static directive to import the static members into the current scope, like this:

using static MyNamespace.MyClass; 

Although this is not what the original question is about, you get a similar error to the one OP gets, so I'm providing it for completeness.

Answer to OP's question:

using is for namespaces only - if both classes are in the same namespace just drop the using.

You have to reference the assembly created in the first step when you compile the .exe:

csc /t:library /out:MyClass.dll MyClass.cs csc /reference:MyClass.dll /t:exe /out:MyProgram.exe MyMainClass.cs 

You can make things simpler if you just compile the files together:

csc /t:exe /out:MyProgram.exe MyMainClass.cs MyClass.cs 

or

csc /t:exe /out:MyProgram.exe *.cs 

EDIT: Here's how the files should look like:

MyClass.cs:

namespace MyNamespace {     public class MyClass {         void stuff() {           }     } } 

MyMainClass.cs:

using System;  namespace MyNamespace {     public class MyMainClass {         static void Main() {             MyClass test = new MyClass();         }     } } 

Answer 2

I know this is very old question but I had the same requirement and just discovered that after c#6 you can use static in using for classes to import.

I hope this helps someone....

using static yourNameSpace.YourClass;