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break (C# Reference)

The break statement terminates the closest enclosing loop or switch statement in which it appears. Control is passed to the statement that follows the terminated statement, if any.

Example

In this example, the conditional statement contains a counter that is supposed to count from 1 to 100; however, the break statement terminates the loop after 4 counts.

class BreakTest
{
    static void Main()
    {
        for (int i = 1; i <= 100; i+)
        {
            if (i == 5)
            {
                break;
            }
            Console.WriteLine(i);
        }

        // Keep the console open in debug mode.
        Console.WriteLine("Press any key to exit.");
        Console.ReadKey();
    }
}
/* 
 Output:
    1
    2
    3
    4  
*/

In this example, the break statement is used to break out of an inner nested loop, and return control to the outer loop.

class BreakInNestedLoops
{
    static void Main(string[] args)
    {

        int[] numbers = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
        char[] letters = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j' };

        // Outer loop 
        for (int x = 0; x < numbers.Length; x+)
        {
            Console.WriteLine("num = {0}", numbers[x]);

            // Inner loop 
            for (int y = 0; y < letters.Length; y+)
            {
                if (y == x)
                {
                    // Return control to outer loop 
                    break;
                }
                Console.Write(" {0} ", letters[y]);
            }
            Console.WriteLine();
        }

        // Keep the console open in debug mode.
        Console.WriteLine("Press any key to exit.");
        Console.ReadKey();
    }
}

/*
 * Output:
    num = 0

    num = 1
     a
    num = 2
     a  b
    num = 3
     a  b  c
    num = 4
     a  b  c  d
    num = 5
     a  b  c  d  e
    num = 6
     a  b  c  d  e  f
    num = 7
     a  b  c  d  e  f  g
    num = 8
     a  b  c  d  e  f  g  h
    num = 9
     a  b  c  d  e  f  g  h  i
 */

This example demonstrates the use of break in a switch statement.

class Switch
{
    static void Main()
    {
        Console.Write("Enter your selection (1, 2, or 3): ");
        string s = Console.ReadLine();
        int n = Int32.Parse(s);

        switch (n)
        {
            case 1:
                Console.WriteLine("Current value is {0}", 1);
                break;
            case 2:
                Console.WriteLine("Current value is {0}", 2);
                break;
            case 3:
                Console.WriteLine("Current value is {0}", 3);
                break;
            default:
                Console.WriteLine("Sorry, invalid selection.");
                break;
        }

        // Keep the console open in debug mode.
        Console.WriteLine("Press any key to exit.");
        Console.ReadKey();
    }
}
/*
Sample Input: 1

Sample Output:
Enter your selection (1, 2, or 3): 1
Current value is 1
*/

If you entered 4, the output would be:

Enter your selection (1, 2, or 3): 4
Sorry, invalid selection.

C# Language Specification

For more information, see the following sections in the C# Language Specification:

  • 5.3.3.10 Break, continue, and goto statements

  • 8.9.1 The break statement

See Also

Concepts

C# Programming Guide

Reference

C# Keywords

The break Statement

switch (C# Reference)

Jump Statements (C# Reference)

Other Resources

C# Reference