C# Switch Case

The C# Switch case or statement is useful to choose a single section from a list of switch sections to execute depending upon the match with the match expression.

In general, C# switch statements are useful in place of if else statements because it is faster than if-else. As we said earlier, the switch case is faster than if-else. Because unlike if else, it prepares a lookup table at compile time to find out the match and directly executes that statement without comparing each condition in the list.

C# Switch Case Syntax

The basic syntax of the C# switch statement is

switch(expression)
{
 case value 1:
 statements;
 break;
 

 case value 2:
 statements;
 break;
 .
 .
 default:
 statements;
}

Let us see an example code using the C# switch case.

using System;
class Switch_Statement
{
     static void Main()
     {
         Console.WriteLine("Enter your character");
         char vowel = char.Parse(Console.ReadLine());

         switch(vowel)
         {
             case ('a'):
                 Console.WriteLine("you entered a vowel");
                 break;
             case ('e'):
                 Console.WriteLine("you entered a vowel");
                 break;
             case ('i'):
                 Console.WriteLine("you entered a vowel");
                 break;
             case ('o'):
                 Console.WriteLine("you entered a vowel");
                 break;
             case ('u'):
                 Console.WriteLine("you entered a vowel");
                 break;
             default:
                 Console.WriteLine("you entered a consonant");
                 break;
         }
     }
}

OUTPUT

Analysis

Here we have taken a char variable vowel to store the character user has entered.

Once we entered i as input. The compiler compares character i with the cases, and the case i will result in the match, and hence it prints the output as

You entered a vowel

Next time, we entered the input as k, which gets matched with neither of the cases and hence it prints the default statement.

You entered a consonant.

C# Switch Case Example

In this example, we are creating a single C# Switch case for Multiple values.

We can create a single case for multiple values when the case statements have no code in between or have a common code for all of them.

A case with no code will fall automatically through the next case.

Let us see the way of coding for the same C# switch case statement example seen above.

using System;
 class Program
 {
   static void Main()
   {
     Console.WriteLine("Enter your character");
     char vowel = char.Parse(Console.ReadLine());
 
     switch(vowel)
     {
       case ('a'):
       case ('e'):
       case ('i'):
       case ('o'):
       case ('u'):
         Console.WriteLine("you entered a vowel");
         break;
       default:
         Console.WriteLine("you entered a consonant");
         break;
     }
   }
 }

OUTPUT

ANALYSIS

Since a, e, i, o, u are all vowels, and have to execute the same code for all these values.

Coming to the C# Switch case execution, we have given i as input for the char variable vowel.

It checks the case i, and because there is no code for i, It falls through o where no code is available. And finally, it falls through u where it finds the code and prints the output.

You entered a vowel

Next, we entered k as input where it founds no match in any of the cases. Hence it prints the default statement.

You entered a consonant