learn c# microsoft – Page 6

C# Variables

Variables are containers for storing data values.

In C#, there are different types of variables (defined with different keywords), for example:

int – stores integers (whole numbers), without decimals, such as 123 or -123
double – stores floating point numbers, with decimals, such as 19.99 or -19.99
char – stores single characters, such as ‘a’ or ‘B’. Char values are surrounded by single quotes
string – stores text, such as “Hello World”. String values are surrounded by double quotes
bool – stores values with two states: true or false

C# Comments

Comments can be used to explain C# code, and to make it more readable. It can also be used to prevent execution when testing alternative code.

Single-line Comments

Single-line comments start with two forward slashes (//).

Any text between // and the end of the line is ignored by C# (will not be executed). Continue reading C# Comments

C# Output

To output values or print text in C#, you can use the WriteLine() method:

Example

Console.WriteLine("Hello World!");

Continue reading C# Output

C# Syntax

In the previous chapter, we created a C# file called Program.cs, and we used the following code to print “Hello World” to the screen:

Program.cs

using System;

namespace HelloWorld
{
  class Program
  {
    static void Main(string[] args)
    {
      Console.WriteLine("Hello World!");    
    }
  }
}

Result:

Hello World!

Continue reading C# Syntax