Java vs. C#

Library & Package

Java
 
// HelloLibrary.java
package Microsoft.CSharp.Introduction;

public class HelloLibrary
{
        
   public String getMessage() {
       return "hello, world";
   }
}

>javac -d HelloLibrary.java
The above command produces a HelloLibrary.class
file stored at Microsoft\CSharp\Introduction\ 
subdirectory

// HelloApp.java
import Microsoft.CSharp.Introduction;
class HelloApp
{
    public static void main(String[] args) {
        HelloLibrary m = new HelloLibrary();
        System.out.println(m.getMessage());
    }
}
>javac HelloApp.java
>java HelloApp
hello, world

C#
 
// HelloLibrary.cs
namespace Microsoft.CSharp.Introduction
{
    public class HelloMessage
    {
        public string Message {
            get {
                return "hello, world";
            }
        }
    }
}
>csc /target:library HelloLibrary.cs
The above command produces a class library HelloLibrary.dll 

// HelloApp.cs
using Microsoft.CSharp.Introduction;
class HelloApp
{
    static void Main() {
        HelloMessage m = new HelloMessage();
        System.Console.WriteLine(m.Message);
    }
}
>csc /reference:HelloLibrary.dll HelloApp.cs
//The above command produces an application HelloApp.exe file
When executed, printout:
hello, world