Reference for unit 'TypInfo'

Access Run-Time Type Information (RTTI).

Overview

The TypInfo unit contains many routines which can be used for the querying of the Run-Time Type Information (RTTI) which is generated by the compiler for classes that are compiled under the {$M+} switch. This information can be used to retrieve or set property values for published properties for totally unknown classes. In particular, it can be used to stream classes. The TPersistent class in the Classes unit is compiled in the {$M+} state and serves as the base class for all classes that need to be streamed.

The unit should be compatible to the Delphi unit with the same name.

The examples in this chapter use a rttiobj auxiliary unit, which contains an object that has a published property for all supported types. It also contains some auxiliary routines and definitions. This unit is included in the documentation sources, in the directory typinfex.

Unit rttiobj;

{$Mode Delphi}
{$M+}

Interface

uses TypInfo;

Const TypeNames : Array [TTYpeKind] of string[15] =
                    ('Unknown','Integer','Char','Enumeration',
                     'Float','Set','Method','ShortString','LongString',
                     'AnsiString','WideString','Variant','Array','Record',
                     'Interface','Class','Object','WideChar','Bool','Int64','QWord',
                     'DynamicArray','RawInterface', 'ProcVar', 'UString', 'UChar',
                     'Helper','File','ClassRef','Pointer');

Const OrdinalTypes = [tkInteger,tkChar,tkENumeration,tkbool];

Type
   TMyEnum = (meFirst,meSecond,meThird);
   TMyEnums = Set of TMyEnum;
   TNotifyEvent = Procedure (Sender : Objectbject;


   TMyTestObject = Class(Objectm
       Private
       FBoolean  : Boolean;
       FByte     : Byte;
       FChar     : Char;
       FWord     : Word;
       FInteger  : Integer;
       Flongint  : Longint;
       FCardinal : Cardinal;
       FReal     : Real;
       FExtended : Extended;
       FMyEnum   : TMyEnum;
       FAnsiString   : AnsiSTring;
       FObj      : Object?
       FNotifyEvent : TNotifyEvent;
       FSetField : TMyEnums;
//       FInt64Field : Int64;
       FInt64Field : Integer;
       FStored   : Boolean;
       Function GetBoolean : Boolean;
       Function GetByte : Byte;
       Function GetChar : Char;
       Function GetWord : Word;
       Function GetInteger : Integer;
       Function GetLongint : Longint;
       Function GetCardinal : Cardinal;
       Function GetReal : Real;
       Function GetExtended : Extended;
       Function GetAnsiString : AnsiString;
       Function GetMyEnum : TMyEnum;
       Procedure SetBoolean ( Value : Boolean);
       Procedure SetByte ( Value : Byte );
       Procedure SetChar ( Value : Char );
       Procedure SetWord ( Value : Word );
       Procedure SetInteger ( Value : Integer );
       Procedure SetLongint ( Value : Longint );
       Procedure SetCardinal ( Value : Cardinal );
       Procedure SetReal ( Value : Real );
       Procedure SetExtended ( Value : Extended );
       Procedure SetAnsiString ( Value : AnsiString );
       Procedure SetMyEnum ( Value : TMyEnum );
       Function GetVirtualBoolean : Boolean; virtual;
       Function GetVirtualByte : Byte; virtual;
       Function GetVirtualChar : Char; virtual;
       Function GetVirtualWord : Word; virtual;
       Function GetVirtualInteger : Integer; virtual;
       Function GetVirtualLongint : Longint; virtual;
       Function GetVirtualCardinal : Cardinal; virtual;
       Function GetVirtualReal : Real; virtual;
       Function GetVirtualExtended : Extended; virtual;
       Function GetVirtualAnsiString : AnsiString; virtual;
       Function GetVirtualMyEnum : TMyEnum; virtual;
       Procedure SetVirtualBoolean ( Value : Boolean); virtual;
       Procedure SetVirtualByte ( Value : Byte ); virtual;
       Procedure SetVirtualChar ( Value : Char ); virtual;
       Procedure SetVirtualWord ( Value : Word ); virtual;
       Procedure SetVirtualInteger ( Value : Integer ); virtual;
       Procedure SetVirtualLongint ( Value : Longint ); virtual;
       Procedure SetVirtualCardinal ( Value : Cardinal ); virtual;
       Procedure SetVirtualReal ( Value : Real ); virtual;
       Procedure SetVirtualExtended ( Value : Extended ); virtual;
       Procedure SetVirtualAnsiString ( Value : AnsiString ); virtual;
       Procedure SetVirtualMyEnum ( Value : TMyEnum ); virtual;
       Function GetStaticStored : Boolean;
       Function GetVirtualStored : Boolean;virtual;
     Public
       Constructor Create;
       Destructor Destroy;override;
       Procedure Notify;
     Published
       Property ObjField: ObjectFObj write FObj;
       Property SetField : TMyEnums Read FSetField Write FSetField;
       Property NotifyEvent : TNotifyEvent Read FNotifyEvent Write FNotifyEvent;
//       Property Int64Field : Int64 Read Fint64Field Write FInt64Field;
       Property Int64Field : Integer Read Fint64Field Write FInt64Field;
       Property BooleanField : Boolean Read FBoolean Write FBoolean;
       Property ByteField : Byte Read FByte Write FByte;
       Property CharField : Char Read FChar Write FChar;
       Property WordField : Word Read FWord Write FWord;
       Property IntegerField : Integer Read FInteger Write FInteger;
       Property LongintField : Longint Read FLongint Write FLongint;
       Property CardinalField : Cardinal Read FCardinal Write FCardinal;
       Property RealField : Real Read FReal Write FReal;
       Property ExtendedField : Extended Read FExtended Write FExtended;
       Property AnsiStringField : AnsiString Read FAnsiString Write FAnsiString;
       Property MyEnumField : TMyEnum Read FMyEnum Write FMyEnum;
       Property BooleanMethod : Boolean Read GetBoolean Write SetBoolean;
       Property ByteMethod : Byte Read GetByte Write SetByte;
       Property CharMethod : Char Read GetChar Write SetChar;
       Property WordMethod : Word Read GetWord Write SetWord;
       Property IntegerMethod : Integer Read GetInteger Write SetInteger;
       Property LongintMethod : Longint Read GetLongint Write SetLongint;
       Property CardinalMethod : Cardinal Read GetCardinal Write SetCardinal;
       Property RealMethod : Real Read GetReal Write SetReal;
       Property ExtendedMethod : Extended Read GetExtended Write SetExtended;
       Property AnsiStringMethod : AnsiString Read GetAnsiString Write SetAnsiString;
       Property MyEnumMethod : TMyEnum Read GetMyEnum Write SetMyEnum;
       Property BooleanVirtualMethod : Boolean Read GetVirtualBoolean Write SetVirtualBoolean;
       Property ByteVirtualMethod : Byte Read GetVirtualByte Write SetVirtualByte;
       Property CharVirtualMethod : Char Read GetVirtualChar Write SetVirtualChar;
       Property WordVirtualMethod : Word Read GetVirtualWord Write SetVirtualWord;
       Property IntegerVirtualMethod : Integer Read GetVirtualInteger Write SetVirtualInteger;
       Property LongintVirtualMethod : Longint Read GetVirtualLongint Write SetVirtualLongint;
       Property CardinalVirtualMethod : Cardinal Read GetVirtualCardinal Write SetVirtualCardinal;
       Property RealVirtualMethod : Real Read GetVirtualReal Write SetVirtualReal;
       Property ExtendedVirtualMethod : Extended Read GetVirtualExtended Write SetVirtualExtended;
       Property AnsiStringVirtualMethod : AnsiString Read GetVirtualAnsiString Write SetVirtualAnsiString;
       Property MyEnumVirtualMethod : TMyEnum Read GetVirtualMyEnum Write SetVirtualMyEnum;
       Property StoredIntegerConstFalse : Longint Read FLongint Stored False;
       Property StoredIntegerConstTrue : Longint Read FLongint Stored True;
       Property StoredIntegerField : Longint Read FLongint Stored FStored;
       Property StoredIntegerMethod : Longint Read Flongint Stored GetStaticStored;
       Property StoredIntegerVirtualMethod : Longint Read Flongint Stored GetVirtualStored;
       end;

  TNamedObject = Class(ObjectMethod 
  Private
    FObjectName : AnsiString;
  Public
    Property ObjectName : AnsiString Read FObjectName Write FObjectName;
  end;

Const
  MyEnumNames : Array[TMyEnum] of string = ('meFirst','meSecond','meThird');

Procedure PrintObject ( Obj: TMyTestObject);

Implementation

Constructor TMyTestObject.Create;

begin
  FBoolean:=true;
  FByte:=1;        {     : Byte;}
  FChar:='B';      {    : Char; }
  FWord:=3;      {: Word;     }
  FInteger:=4;     {: Integer;  }
  Flongint:=5;     { : Longint; }
  FCardinal:=6;    {: Cardinal; }
  FReal:=7.0;      {     : Real;}
  FExtended :=8.0; { Extended;}
  FMyEnum:=methird; { TMyEnum;}
  FAnsiString:='this is an AnsiString';
end;

Destructor TMyTestObject.Destroy;

begin
  Inherited Destroy;
end;

Function TMyTestObject.GetBoolean : boolean;

begin
  Result:=FBoolean;
end;

Function TMyTestObject.GetByte : Byte;

begin
  Result:=FByte;
end;

Function TMyTestObject.GetChar : Char;
begin
  Result:=FChar;
end;

Function TMyTestObject.GetWord : Word;
begin
  Result:=FWord;
end;

Function TMyTestObject.GetInteger : Integer;
begin
  Result:=FInteger;
end;

Function TMyTestObject.GetLongint : Longint;
begin
  Result:=FLongint;
end;

Function TMyTestObject.GetCardinal : Cardinal;
begin
  Result:=FCardinal;
end;

Function TMyTestObject.GetReal : Real;
begin
  Result:=FReal;
end;

Function TMyTestObject.GetExtended : Extended;
begin
  Result:=FExtended;
end;

Function TMyTestObject.GetAnsiString : AnsiString;
begin
  Result:=FAnsiString;
end;

Function TMyTestObject.GetMyEnum : TMyEnum;
begin
  Result:=FMyEnum;
end;

Procedure TMyTestObject.Setboolean ( Value : boolean );
begin
  Fboolean:=Value;
end;


Procedure TMyTestObject.SetByte ( Value : Byte );
begin
  FByte:=Value;
end;

Procedure TMyTestObject.SetChar ( Value : Char );
begin
  FChar:=Value;
end;

Procedure TMyTestObject.SetWord ( Value : Word );
begin
  FWord:=Value;
end;

Procedure TMyTestObject.SetInteger ( Value : Integer );
begin
  FInteger:=Value;
end;

Procedure TMyTestObject.SetLongint ( Value : Longint );
begin
  FLongint:=Value;
end;

Procedure TMyTestObject.SetCardinal ( Value : Cardinal );
begin
  FCardinal:=Value;
end;

Procedure TMyTestObject.SetReal ( Value : Real );
begin
  FReal:=Value;
end;

Procedure TMyTestObject.SetExtended ( Value : Extended );
begin
  FExtended:=Value;
end;

Procedure TMyTestObject.SetAnsiString ( Value : AnsiString );
begin
  FAnsiString:=Value;
end;

Procedure TMyTestObject.SetMyEnum ( Value : TMyEnum );
begin
  FMyEnum:=Value;
end;

Function TMyTestObject.GetVirtualBoolean : boolean;

begin
  Result:=FBoolean;
end;

Function TMyTestObject.GetVirtualByte : Byte;

begin
  Result:=FByte;
end;

Function TMyTestObject.GetVirtualChar : Char;
begin
  Result:=FChar;
end;

Function TMyTestObject.GetVirtualWord : Word;
begin
  Result:=FWord;
end;

Function TMyTestObject.GetVirtualInteger : Integer;
begin
  Result:=FInteger;
end;

Function TMyTestObject.GetVirtualLongint : Longint;
begin
  Result:=FLongint;
end;

Function TMyTestObject.GetVirtualCardinal : Cardinal;
begin
  Result:=FCardinal;
end;

Function TMyTestObject.GetVirtualReal : Real;
begin
  Result:=FReal;
end;

Function TMyTestObject.GetVirtualExtended : Extended;
begin
  Result:=FExtended;
end;

Function TMyTestObject.GetVirtualAnsiString : AnsiString;
begin
  Result:=FAnsiString;
end;

Function TMyTestObject.GetVirtualMyEnum : TMyEnum;
begin
  Result:=FMyEnum;
end;

Procedure TMyTestObject.SetVirtualboolean ( Value : boolean );
begin
  Fboolean:=Value;
end;


Procedure TMyTestObject.SetVirtualByte ( Value : Byte );
begin
  FByte:=Value;
end;

Procedure TMyTestObject.SetVirtualChar ( Value : Char );
begin
  FChar:=Value;
end;

Procedure TMyTestObject.SetVirtualWord ( Value : Word );
begin
  FWord:=Value;
end;

Procedure TMyTestObject.SetVirtualInteger ( Value : Integer );
begin
  FInteger:=Value;
end;

Procedure TMyTestObject.SetVirtualLongint ( Value : Longint );
begin
  FLongint:=Value;
end;

Procedure TMyTestObject.SetVirtualCardinal ( Value : Cardinal );
begin
  FCardinal:=Value;
end;

Procedure TMyTestObject.SetVirtualReal ( Value : Real );
begin
  FReal:=Value;
end;

Procedure TMyTestObject.SetVirtualExtended ( Value : Extended );
begin
  FExtended:=Value;
end;

Procedure TMyTestObject.SetVirtualAnsiString ( Value : AnsiString );
begin
  FAnsiString:=Value;
end;

Procedure TMyTestObject.SetVirtualMyEnum ( Value : TMyEnum );
begin
  FMyEnum:=Value;
end;

Function TMyTestObject.GetStaticStored : Boolean;

begin
  Result:=False;
end;

Function TMyTestObject.GetVirtualStored : Boolean;

begin
  Result:=False;
end;

Procedure TMyTestObject.Notify;

begin
  If Assigned(FNotifyEvent) then
    FNotifyEvent(Self)
  else
    Writeln('Error : No notifyevent assigned');
end;


Procedure PrintObject ( Obj: TMyTestObject);

begin
  With Obj do
    begin
    Writeln ('Field properties :');
    Writeln ('Property booleanField    : ',booleanField);
    Writeln ('Property ByteField       : ',ByteField);
    Writeln ('Property CharField       : ',CharField);
    Writeln ('Property WordField       : ',WordField);
    Writeln ('Property IntegerField    : ',IntegerField);
    Writeln ('Property LongintField    : ',LongintField);
    Writeln ('Property CardinalField   : ',CardinalField);
    Writeln ('Property RealField       : ',RealField);
    Writeln ('Property ExtendedField   : ',ExtendedFIeld);
    Writeln ('Property AnsiStringField : ',AnsiStringField);
    Writeln ('Property MyEnumField     : ',ord(MyEnumField));
    Writeln ('Method properties :');
    Writeln ('Property booleanMethod    : ',BooleanMethod);
    Writeln ('Property ByteMethod       : ',ByteMethod);
    Writeln ('Property CharMethod       : ',CharMethod);
    Writeln ('Property WordMethod       : ',WordMethod);
    Writeln ('Property IntegerMethod    : ',IntegerMethod);
    Writeln ('Property LongintMethod    : ',LongintMethod);
    Writeln ('Property CardinalMethod   : ',CardinalMethod);
    Writeln ('Property RealMethod       : ',RealMethod);
    Writeln ('Property ExtendedMethod   : ',ExtendedMethod);
    Writeln ('Property AnsiStringMethod : ',AnsiStringMethod);
    Writeln ('Property MyEnumMethod     : ',ord(MyEnumMethod));
    Writeln ('VirtualMethod properties :');
    Writeln ('Property booleanVirtualMethod    : ',BooleanVirtualMethod);
    Writeln ('Property ByteVirtualMethod       : ',ByteVirtualMethod);
    Writeln ('Property CharVirtualMethod       : ',CharVirtualMethod);
    Writeln ('Property WordVirtualMethod       : ',WordVirtualMethod);
    Writeln ('Property IntegerVirtualMethod    : ',IntegerVirtualMethod);
    Writeln ('Property LongintVirtualMethod    : ',LongintVirtualMethod);
    Writeln ('Property CardinalVirtualMethod   : ',CardinalVirtualMethod);
    Writeln ('Property RealVirtualMethod       : ',RealVirtualMethod);
    Writeln ('Property ExtendedVirtualMethod   : ',ExtendedVirtualMethod);
    Writeln ('Property AnsiStringVirtualMethod : ',AnsiStringVirtualMethod);
    Writeln ('Property MyEnumVirtualMethod     : ',ord(MyEnumVirtualMethod));
    end;
end;

Procedure DumpMem ( PL : PByte );

Var I,j : longint;

begin
  or:=1 to 16 do
    begin
    Write ((I-1)*16:3,' :');
    or:=1 to 10  do
      begin
      If (PL^>31) and (PL^<129) then
         Write('  ',CHar(PL^))
      else
        Write (PL^:3);
      Write (' ');
      inc(pl);
      end;
    writeln;
    end;
end;


Function ProcType (PP : Byte) : String;

begin
  Case PP and 3 of
    ptfield   : Result:='from Field';
    ptstatic  : Result:='with static method';
    ptVirtual : Result:='with virtual method';
    ptconst   : Result:='with Const';
   end;
end;

end.

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