C# goto

In C#, the goto statement transfers control to some other part of the program. For example,

goto label;
... 
...
label:
  ...
  ...

Here, label is an identifier. When goto label; is encountered, the control of the program is transferred to label:. Then the code below label: is executed.

Example: C# goto

using System;

namespace CSharpGoto {

  class Program {
    public static void Main(string[] args) {
      
      // label
      repeat: 
        Console.WriteLine("Enter a number less than 10");
        int num = Convert.ToInt32(Console.ReadLine());  

        if(num >= 10) {
          // transfers control to repeat
          goto repeat;
        }

        Console.WriteLine(num + " is less than 10");
        Console.ReadLine();
    }
  }
}

Output

Enter a number less than 10
99
Enter a number less than 10
9
9 is less than 10

In the above program, we have a goto statement inside the if statement.

If the entered number is not less than 10, goto repeat: transfers the control of the code to repeat:. Then, the code below repeat: is executed.

The control of code will be transferred to the repeat: label unless the entered number is less than 10.

C# goto with switch statement

In C#, we can use goto with a switch statement to transfer control of a program to a specific case. For example,

using System;

namespace CSharpGoto {

  class Program {

    public static void Main(string[] args) {

      Console.Write("Choose your coffee? milk or black: ");
      string coffeeType = Console.ReadLine();

      switch (coffeeType) {
        case "milk":
          Console.WriteLine("Can I have a milk coffee?");
          break;

        case "black":
          Console.WriteLine("Can I have a black coffee?");
          // transfer code to case "milk" 
          goto case "milk";
     
        default:
          Console.WriteLine("Not available.");
            break;
        }
      Console.ReadLine();
    }
  }
}

Output

Can I have a black coffee?
Can I have a milk coffee?

In the above program, we have used the goto statement with a switch statement.

We have entered "black" as the coffeeType. Now the case "black" is executed.

Inside the case, we have used goto case "milk"; which will transfer the control of the program to the case "milk".

Hence, both cases are executed.

goto with for Loop

In C#, we can use goto to break out of a for loop. For example,

using System;

namespace CSharpGoto {

  class Program {

    static void Main() {
    for(int i = 0; i <= 10; i++) {

      if(i == 5) {
        // transfers control to End label
        goto End;
      }

      Console.WriteLine(i);
    }

    // End label
    End:
      Console.WriteLine("Loop End");
      Console.ReadLine();
    }
  }
}

Output

0
1
2
3
4
Loop End

In the above program, we have created a for loop. It iterates from 0 to 100.

Whenever the value of i equals 5, the goto statement transfers the control of code to the End label. Hence, the program breaks out of the for loop.