Boolean type behavior in C Sharp (C#)

Introduction

Booleans help us make decisions in code by representing true or false values.

Checking if a user is logged in or not.

Deciding if a light switch is on or off.

Verifying if a password is correct.

Controlling if a game character is alive or dead.

Determining if a form input is valid.

Syntax

C Sharp (C#)

bool variableName = true; // or false

Boolean variables can only hold true or false.

Use booleans to control program flow with if statements.

Examples

This creates a boolean variable named isRaining and sets it to true.

C Sharp (C#)

bool isRaining = true;

This creates a boolean variable named hasFinished and sets it to false.

C Sharp (C#)

bool hasFinished = false;

This sets isAdult to true if age is 18 or more, otherwise false.

C Sharp (C#)

bool isAdult = age >= 18;

Sample Program

This program shows how a boolean variable isDoorOpen controls the message printed. It starts false, then changes to true, and the if statement checks it.

C Sharp (C#)

using System;

class Program
{
    static void Main()
    {
        bool isDoorOpen = false;
        Console.WriteLine("Is the door open? " + isDoorOpen);

        isDoorOpen = true;
        if (isDoorOpen)
        {
            Console.WriteLine("You can enter the room.");
        }
        else
        {
            Console.WriteLine("The door is closed.");
        }
    }
}

Important Notes

Boolean values are case-sensitive: use true and false in lowercase.

Booleans are often used in if, while, and for statements to control flow.

Summary

Booleans store only two values: true or false.

They help your program make decisions.

Use them with conditions to control what your program does.