C# switch case constructs

Switch case is also another condition constructs in C# programming that evaluates the condition as if else but only difference is that it makes program simpler and easier. It is used when there is multiple if condition in a program. It also includes a default value in Default statements. If no any case matches then Default statements executes and run the code.

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using System;

namespace Switch_Case
{
  class Program
   {
     static void Main(string[] args)
      {
        int opt, num1, num2;
        float result;

        label:

        Console.WriteLine("\n\tMenu");
        Console.WriteLine("\nPress 1 for add");
        Console.WriteLine("Press 2 for subtraction");
        Console.WriteLine("Press 3 for multiplication");
        Console.WriteLine("Press 4 for Division");
  
        Console.Write("\n\nEnter first number:\t");
        num1 = Convert.ToInt32(Console.ReadLine());

        Console.Write("Enter second number:\t");
        num2 = Convert.ToInt32(Console.ReadLine());

        Console.Write("\nEnter your option:\t");
        opt = Convert.ToInt32(Console.ReadLine());

        switch (opt)
         {
           case 1:
               result = num1 + num2;
               Console.WriteLine("\n{0} + {1} = {2}", num1, num2, result);
               break;

           case 2:
               result = num1 - num2;
               Console.WriteLine("\n{0} - {1} = {2}", num1, num2, result);
               break;
           case 3:
               result = num1 * num2;
               Console.WriteLine("\n{0} * {1} = {2}", num1, num2, result);
               break;
           case 4:
               result = (float)num1 / num2;
               Console.WriteLine("\n{0} / {1} = {2}", num1, num2, result);
               break;
           default:
                   Console.WriteLine("\nInvalid option Please try again.");
                   goto label;
         }
        Console.ReadLine();
      }
   }
}

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Output

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        Menu

Press 1 for add
Press 2 for subtraction
Press 3 for multiplication
Press 4 for Division


Enter first number :       22
Enter second number :   8

Enter your option:          4

22 / 8 = 2.75

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Guideline to use Switch case:

1. Must include break statement in each case and default statements.
2. If you are accepting char value then write it within single quotes as follow:
case ‘1’, case ‘b’, case ‘c’, case ‘k’ etc.
3.If you are accepting string value then write it within double quotes as follow:
case “add”, case “sub”, case “mul”, case “div” etc.