(constructor) (Destructor). Delphi Create() Destroy(). Create ( ), Destroy() .
Type
TMyClass= class
FIntField: Integer;
Constructor Create(Value:Integer);
Destructor Destroy;
End;
, , , .
Var
MyObject: TMyClass;
Begin
MyObject.FIntField:= 0; //.
// ,
MyObject:= TMyClass.Create; //.
MyObject.FIntField:= 0; //
MyObject.Free; //
End;
TObject Free, Destroy.
If Self<>Nil then Destroy;
self .
System FreeAndNil, ,
Nil.
FreeAndNil(MyObject);
, . inherited()
Constructor TMyClass.Create(AOwner:TComponent;Value:integer);
//
Begin
Inherited Crete(Aowner:TComponent);//
intField:=Value;//
End;
, . , .
Overload.
Type
T1=class(TObject)
Procedure Sum(X,Y:Integer);overload;
End;
T2=class(T1)
Procedure Sum(X,Y:Real);overload;
End;
Var Ct:T2;
Begin
Ct:=T2.Creat;
Ct.Sum(2,2); // T1.sum()
Ct.Sum(2.0,2.0);// T2.sum()
End;
reintroduce.
Type
T1=class(TObject)
Procedure Sum(X,Y:Integer);overload; virtual;
End;
T2=class(T1)
Procedure Sum(X,Y:Real);reintroduce; overload;
End;
. , class.
Type
TMyclass=class(TObject)
Class Function GetClassName:String;
End;
Var
S:String;
Begin
S:=TMyClass.GetClassName;
End;
, . Property, read write( read write ). , .
|
|
Type
TaClass=Class
IntField:Integer;
Function GetField:integer;
Procedure SetField(Value:integer);
Property IntegrValue:integer read GetField write SetFeild;
End;
. ,
var
aclass:Taclass;
Value:integer;
Begin
Aclass:= Taclass.Create;//
//
Aclass.IntegerValue:=0;
Value:= aclass.IntegerValue;
Aclass.Destroy;//
End;
, , write read.
, published (), private (), protected (), public (), automated ().
, .
. public , . published , . private , , , . Protected .
Type
TForm = class (TForm)
Button1:Tbutton;//
Private //
FintField:integer;
Procedure SetValue(Value:Integer);
FunctionGetValue:integer;
Published //
Property intField read GetValue write SetValue
Protected //
//
Procedure Proc1;
Public //
Procedure Proc2;
End;