RETURN VALUES

Methods can return a value to the caller. If the return type, the type listed before the method name, is not void, the method can return the value by using the return keyword. A statement with the return keyword followed by a value that matches the return type will return that value to the method caller. The return keyword also stops the execution of the method. If the return type is void, a return statement without a value is still useful to stop the execution of the method. Without the return keyword, the method will stop executing when it reaches the end of the code block. Methods with a non-void return type are required to use the return keyword to return a value. For example, these two methods use the return keyword to return integers:

class SimpleMath

{

    public int AddTwoNumbers(int number1, int number2)

    {

        return number1 + number2;

    }

    public int SquareANumber(int number)

    {

        return number * number;

    }

}

To use a value returned from a method, the calling method can use the method call itself anywhere a value of the same type would be sufficient. You can also assign the return value to a variable. For example, the following two code examples accomplish the same goal:

int result = obj.AddTwoNumbers(1, 2);

result = obj.SquareANumber(result);

// The result is 9.

Console.WriteLine(result);

result = obj.SquareANumber(obj.AddTwoNumbers(1, 2));

// The result is 9.

Console.WriteLine(result);

Using an local variable, in this case, result, to store a value is optional. It may help the readability of the code, or it may be necessary if you need to store the original value of the argument for the entire scope of the method.