In this first example, you will create a very simple application that does nothing more than display the words “Hello World” to your monitor. This console application is the traditional first program for learning any new language; it demonstrates some of the basic elements of a C# program.
Once you write your “Hello World” program and compile it, this chapter will provide a line-by-line analysis of the source code. This analysis gives something of a preview of the language; Chapter 3 describes the fundamentals much more fully.
As explained earlier, you can create C# programs with any text editor. You can, for example, create each of the three programs shown previously (in Figures 1-1, 1-2, and 1-3) with Notepad. To demonstrate that this is possible, you’ll write your very first C# program using Notepad.
Begin by opening Notepad and typing in the program exactly as shown in Example 1-2.
Example 1-2. Hello World in Notepad
namespace NotePad { class HelloWorld { // every console app starts with Main static void Main( ) { System.Console.WriteLine("Hello world!"); } } }
That is the entire program. Save it to your disk as a file called helloworld.cs.
We’ll examine this program in some detail in just a moment. First, however, it must be compiled.