In C#, the switch statement is a control flow statement that allows you to execute different blocks of code based on the value of a variable or expression. Here’s a basic example to illustrate its usage:

using System;

class Program
{
    static void Main()
    {
        int day = 3;
        string dayName;

        switch (day)
        {
            case 1:
                dayName = "Monday";
                break;
            case 2:
                dayName = "Tuesday";
                break;
            case 3:
                dayName = "Wednesday";
                break;
            case 4:
                dayName = "Thursday";
                break;
            case 5:
                dayName = "Friday";
                break;
            case 6:
                dayName = "Saturday";
                break;
            case 7:
                dayName = "Sunday";
                break;
            default:
                dayName = "Invalid day";
                break;
        }

        Console.WriteLine(dayName);
    }
}

Explanation:

• Variable: In this example, we have an integer variable day which is being evaluated.

• Cases: Each case corresponds to a specific value that day can take.

• Break Statement: The break statement is used to exit the switch block once a matching case is found and executed.

• Default Case: The default case is optional and will execute if none of the specified cases match.

Exercise 1: Grade Calculator

Write a program that takes a numeric score (0-10) and uses a switch statement to determine the corresponding letter grade.

Example input: 5
// Example output: F

Exercise 2: Month Name

Create a program that asks the user for a month number (1-12) and prints the corresponding month name.

Example input: 4
// Example output: April

Exercise 3: Simple Calculator

Implement a simple calculator that takes two numbers and an operator (+, -, *, /) from the user and uses a switch statement to perform the calculation.

Example input: 10, 5, +
// Example output: 15

Exercise 4: Days in a Month

Write a program that asks for a month number (1-12) and uses a switch statement to print how many days are in that month (considering February has 28 days).

Example input: 2
// Example output: 28 days

Exercise 5: Traffic Light

Create a program that takes an input for a traffic light color (Red, Yellow, Green) and uses a switch statement to print the action to take (Stop, Caution, Go).

Example input: Green
// Example output: Go

Solutions to the exercises

Exercise 1: Grade Calculator

using System;

class GradeCalculator
{
    static void Main()
    {
        Console.Write("Enter your score (0-10): ");
        int score = int.Parse(Console.ReadLine());
        char grade;

        switch (score)
        {
            case 10:
            case 9:
                grade = 'A';
                break;
            case 8:
                grade = 'B';
                break;
            case 7:
                grade = 'C';
                break;
            case 6:
                grade = 'D';
                break;
            case 5:
            case 4:
            case 3:
            case 2:
            case 1:
            case 0:
                grade = 'F';
                break;
            default:
                Console.WriteLine("Invalid score.");
                return;
        }

        Console.WriteLine("Your grade is: "+grade);
    }
}

Exercise 2: Month Name

using System;

class MonthName
{
    static void Main()
    {
        Console.Write("Enter a month number (1-12): ");
        int month = int.Parse(Console.ReadLine());
        string monthName;

        switch (month)
        {
            case 1: monthName = "January"; break;
            case 2: monthName = "February"; break;
            case 3: monthName = "March"; break;
            case 4: monthName = "April"; break;
            case 5: monthName = "May"; break;
            case 6: monthName = "June"; break;
            case 7: monthName = "July"; break;
            case 8: monthName = "August"; break;
            case 9: monthName = "September"; break;
            case 10: monthName = "October"; break;
            case 11: monthName = "November"; break;
            case 12: monthName = "December"; break;
            default: monthName = "Invalid month"; break;
        }

        Console.WriteLine(monthName);
    }
}

Exercise 3: Simple Calculator

using System;

class SimpleCalculator
{
    static void Main()
    {
        Console.Write("Enter first number: ");
        double num1 = double.Parse(Console.ReadLine());
        Console.Write("Enter second number: ");
        double num2 = double.Parse(Console.ReadLine());
        Console.Write("Enter operator (+, -, *, /): ");
        char operation = Console.ReadLine();
        double result;

        switch (operation)
        {
            case '+': result = num1 + num2; break;
            case '-': result = num1 - num2; break;
            case '*': result = num1 * num2; break;
            case '/':
                if (num2 != 0)
                    result = num1 / num2;
                else
                {
                    Console.WriteLine("Error: Division by zero.");
                    return;
                }
                break;
            default:
                Console.WriteLine("Invalid operator.");
                return;
        }

        Console.WriteLine("Result:" + result);
    }
}

Exercise 4: Days in a Month

using System;

class DaysInMonth
{
    static void Main()
    {
        Console.Write("Enter a month number (1-12): ");
        int month = int.Parse(Console.ReadLine());
        int days;

        switch (month)
        {
            case 1: case 3: case 5: case 7: case 8: case 10: case 12:
                days = 31; break;
            case 4: case 6: case 9: case 11:
                days = 30; break;
            case 2:
                days = 28; break; // Not accounting for leap years
            default:
                Console.WriteLine("Invalid month.");
                return;
        }

        Console.WriteLine(days +"days");
    }
}

Exercise 5: Traffic Light

using System;

class TrafficLight
{
    static void Main()
    {
        Console.Write("Enter traffic light color (Red, Yellow, Green): ");
        string color = Console.ReadLine()?.ToLower();
        string action;

        switch (color)
        {
            case "red":
                action = "Stop"; break;
            case "yellow":
                action = "Caution"; break;
            case "green":
                action = "Go"; break;
            default:
                action = "Invalid color"; break;
        }

        Console.WriteLine(action);
    }
}