Topics covered:

  • Using Methods
    • What is a Method? Why to Use Methods?
    • Declaring and Creating Methods
    • Calling Methods
  • Methods with Parameters
    • Passing Parameters
    • Returning Values
  • Best Practices

Video (in Bulgarian)

Presentation Content

What is a Method?

  • A method is a kind of building block that solves a small problem
    • A piece of code that has a name and can be called from the other code
    • Can take parameters and return a value
  • Methods allow programmers to construct large programs from simple pieces
  • Methods are also known as functions , procedures , and subroutines

Why to Use Methods?

  • More manageable programming
    • Split large problems into small pieces
    • Better organization of the program
    • Improve code readability
    • Improve code understandability
  • Avoiding repeating code
    • Improve code maintainability
  • Code reusability
    • Using existing methods several times

Declaring and Creating Methods

  • Each method has a name
    • It is used to call the method
    • Describes its purpose
  • Methods declared static can be called by any other method (static or not)
    • This will be discussed later in details
  • The keyword void means that the method does not return any result

Calling Methods

  • To call a method, simply use:
    • The method’s name
    • Parentheses (don’t forget them!)
    • A semicolon ( ; )
  • This will execute the code in the method’s body and will result in printing the following:
  • A method can be called from:
    • The Main() method
    • Any other method
    • Itself (process known as recursion )

Method Parameters

  • To pass information to a method, you can use _parameters _ (also known as arguments )
    • You can pass zero or several input values
    • You can pass values of different types
    • Each parameter has name and type
    • Parameters are assigned to particular values when the method is called
  • Parameters can change the method behavior depending on the passed values

Calling Methods with Parameters

  • To call a method and pass values to its parameters:
    • Use the method’s name, followed by a list of expressions for each parameter
  • Expressions must be of the same type as method’s parameters (or compatible)
    • If the method requires a float expression, you can pass int instead
  • Use the same order like in method declaration
  • For methods with no parameters do not forget the parentheses

Returning Values From Methods

  • A method can return a value to its caller
  • Returned value:
    • Can be assigned to a variable
    • Can be used in expressions
    • Can be passed to another method

Defining Methods That Return a Value

  • Instead of void , specify the type of data to return
  • Methods can return any type of data ( int , string , array, etc.)
  • void methods do not return anything
  • The combination of method’s name and parameters is called method signature
  • Use return keyword to return a result

The return Statement

  • The return statement:
    • Immediately terminates method’s execution
    • Returns specified expression to the caller
  • To terminate void method, use just:
  • Return can be used several times in a method body

Methods – Best Practices

  • Each method should perform a single, well-defined task
  • Method’s name should describe that task in a clear and non-ambiguous way
    • Good examples: CalculatePrice , ReadName
    • Bad examples: f , g1 , Process
    • In C# methods should start with capital letter
  • Avoid methods longer than one screen
    • Split them to several shorter methods


  • Break large programs into simple methods that solve small sub-problems
  • Methods consist of declaration and body
  • Methods are invoked by their name
  • Methods can accept parameters
    • Parameters take actual values when calling a method
  • Methods can return a value or nothing