Delphi class example

Class example
A basic example of class creation.

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Class example

For us Delphi beginners, here's an example of some of the features to use when making your own class. The uses section should obviously reflect the classes you want the class to use.

unit UnitName;
{ ----- Delphi Class example ----- }
interface

// Change the uses clause as necessary
uses Windows,Messages,Classes,SysUtils;

type

TMyClass = class
  private
    variable1 : String;
    function  PrivFunc(param1: integer;param2 : integer): string;
    procedure PrivProc();
  public
    variable2 : String;

constructor Create();
    destructor Destroy();
    function  PubFunc():String;

{ var passes by reference }
    procedure PubProc(var param1a: String;param2a: String);
  protected
    {
      Protected methods/properties cannot be
      accessed by users of the class, but can
      be accessed by classes that are derived from
      the class
    }
  published
    {
      Published methods/properties are used when
      writing Delphi components. Any properties and
      methods put here appear in the Object Inspector
      at design time
    }
  end;

{ ----- Here is an example of inheritence ----- }
  // Inherits TMyClass
  TMyClassInherited = class(TMyClass)
  private
    // Your private methods/properties here
    // NOTE: If you have the derived classes' definition
    // in the same unit as the base class, private methods
    // of the original base class aren't inherited, only
    // protected one.
  public
    // Your public methods/properties here
    // and so on....

// Over-riden method
    procedure PubProc(var param1a: String;param2a: String);
  end;

implementation

constructor TMyClass.Create();
begin
     // Initialise whatever needs initialising
end;

procedure TMyClass.PubProc(var param1a: string;param2a: string);
begin
	// code here
end;

function TMyClass.PubFunc():String;
begin
 // code here
end;

function TMyClass.PrivFunc(param1: integer;param2 : integer): string;
begin
 // code here
end;

procedure TMyClass.PrivProc();
begin
	// code here
end;

destructor TMyClass.Destroy();
begin
     // when the class is destroyed, clean up what needs cleaning.
end;

procedure TMyClassInherited.PubProc(var param1a: String;param2a: String);
begin
    // Inherit all the functionality of the original method like this
    inherited PubProc(param1a,param2a);
end;

end.