Video: Methods in C# (Bulgarian)

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

Summary

• 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