Functions in C#

A function is a reusable block of code that performs a specific task. It helps divide a program into smaller parts, making it easier to read and maintain. It can take input (parameters), execute code, and optionally return a value.

• Promotes code reusability by avoiding repetition
• Improves readability and structure of the program
• Makes code easier to manage and maintain

Square of 5 is: 25

Function Syntax in C#

A function in C# follows this general format:

Each part has a specific role:

• Return type: Specifies the type of value returned. Use void if no value is returned.
• Function name: Name used to call the function.
• Parameter list: Inputs accepted by the function.
• Function body: Code executed when the function is called.

Function Declaration vs Definition

In C#, functions (methods) are usually declared and defined together inside a class.

Unlike C++, C# does not require separate declaration and definition in different files, methods are typically declared and defined together inside a class.

Calling a Function

A function is used by calling its name followed by parentheses, passing arguments if required.

Welcome to C# Programming!
Multiplication result: 20

• Greet() is a parameterless method that prints a message.
• Multiply(int a, int b) takes two integers and returns their product.
• Functions are called inside Main() using their names.

Types of Functions in C#

Functions in C# can be categorized as:

1. Based on Origin

• Library Methods: Built-in methods provided by .NET, such as Console.WriteLine() and Math.Sqrt().
• User-Defined Functions: Functions created by the programmer.

2. Based on Input and Return Type

• No parameters, no return value
• Parameters, no return value
• No parameters, return value
• Parameters and return value

Note: Choosing the correct type of function improves code readability and flexibility. Functions help in reusing code and organizing large programs efficiently.