C# Methods

Introduction

Have you heard about functions in C#? In C#, functions and methods are often used interchangeably. Both refer to a block of code that performs a specific task. This code block is defined by a signature and contains statements that are executed sequentially.

Main Components of a Function/Method

A function/method in C# consists of the following main parts:

1. Access Modifier: Defines the visibility of the function, such as public, private, protected, etc.
2. Return Type: Specifies the type of value that the function returns. If the function does not return a value, the return type is void.
3. Function Name: The name of the function, which is used to call it.
4. Parameters: A list of parameters (if any) that the function takes as input.
5. Body: The block of code that executes the function’s statements.

Mathematical Functions

C# provides several built-in mathematical functions that are part of the Math class:

• Math.Abs(): Returns the absolute value of a given number.

  int number = -5;
  int absoluteValue = Math.Abs(number);
  Console.WriteLine(absoluteValue); // Output: 5

• Math.Floor() & Math.Ceiling(): Return the floor (largest integer less than or equal to the number) and ceiling (smallest integer greater than or equal to the number) of a specified number.

  double number = 7.8;
  Console.WriteLine(Math.Floor(number)); // Output: 7
  Console.WriteLine(Math.Ceiling(number)); // Output: 8

• Math.DivRem(dividend, divisor, out remainder): Returns the quotient of the division and stores the remainder in the out parameter.

  int dividend = 10;
  int divisor = 3;
  int remainder;
  int quotient = Math.DivRem(dividend, divisor, out remainder);
  Console.WriteLine($"Quotient: {quotient}, Remainder: {remainder}"); // Output: Quotient: 3, Remainder: 1

• Math.Min() & Math.Max(): Return the smallest and largest values among the given arguments.

  int a = 5, b = 10;
  Console.WriteLine(Math.Min(a, b)); // Output: 5
  Console.WriteLine(Math.Max(a, b)); // Output: 10

• Math.Pow(base, exponent): Returns the result of raising a number to a specified power.

  double result = Math.Pow(2, 3);
  Console.WriteLine(result); // Output: 8

• Math.Round(): Rounds a number to the nearest integer or to a specified number of decimal places.

  double number = 5.678;
  Console.WriteLine(Math.Round(number)); // Output: 6

• Math.Sqrt(): Returns the square root of the given number.

  double number = 16;
  Console.WriteLine(Math.Sqrt(number)); // Output: 4

Generating Random Numbers

In C#, the Random class is used to generate random numbers. Here’s an example:

Random rand = new Random();
Console.WriteLine("Random number between 1 and 10: " + rand.Next(1, 11));
Console.ReadKey();

User-Defined Functions

C# allows you to define your own functions. Below are examples of the four main types of user-defined functions:

1. Function with No Arguments and No Return Value:

   public void PrintMessage()
   {
       Console.WriteLine("Hello, World!");
   }

   Usage:

   PrintMessage(); // Output: Hello, World!

2. Function with No Arguments and a Return Value:

   public int GetRandomNumber()
   {
       Random rand = new Random();
       return rand.Next(1, 101);
   }

   Usage:

   int number = GetRandomNumber();
   Console.WriteLine("Random Number: " + number);

3. Function with Arguments and No Return Value:

   public void PrintSum(int a, int b)
   {
       int sum = a + b;
       Console.WriteLine("Sum: " + sum);
   }

   Usage:

   PrintSum(5, 10); // Output: Sum: 15

4. Function with Arguments and a Return Value:

   public int Multiply(int a, int b)
   {
       return a * b;
   }

   Usage:

   int result = Multiply(4, 5);
   Console.WriteLine("Product: " + result); // Output: Product: 20