C# Basics: Hello, .NET

CSC-378 · Semester VI · .NET Centric Computing

beginner15 minAvailable

C# / .NETin-browser interpreter · runs locally

using System;

class Program {
  static void Main() {
    Console.WriteLine("Hello, World!");
    Console.Write("Enter your name: ");
    string name = Console.ReadLine();
    Console.WriteLine("Hello, " + name + "!");
  }
}

11 lines

Output

Write some code, then press Run. Stdout and errors appear here.

Lab brief

Objective

Write, compile and run your first C# program in the .NET environment and get comfortable with Console I/O.

Theory & concepts

C# is compiled to IL (intermediate language) and executed by the Common Language Runtime (CLR), part of the .NET runtime. A simple console program defines a class with a static Main method, the entry point the CLR calls first.

Rendering diagram…

From C# source to execution on the CLR

Console.WriteLine prints a line to standard output, and Console.ReadLine reads a line of input. C# is statically typed: every variable has a type chosen at compile time, such as int, double or string.

Prerequisites

Lesson: Introduction to .NET and C#
Lesson: The .NET runtime and CLR

Instructions

1Inspect the starter code: a Program class with a static Main method.
2Run it and confirm the console shows Hello, World!.
3Change the message to include your name.
4Add a line that reads your name with Console.ReadLine and greets you.
5Run again and observe that the output adapts to your input.

Tasks

Run the starter
Run the program and confirm Hello, World! appears.
Personalize it
Change the message to greet you by name.
Read input
Read your name with ReadLine and print a personalized greeting.

Self-check

The program compiles and runs.
The student can explain the role of Main.
The student can use WriteLine and ReadLine correctly.
The student can explain the difference between a value and a string literal.

Environment

editorstdout consolestdin