point.pas

《Kylix程序设计》一书中附带的例程源代码

unit Point;

interface

type
  TMyData = record
    X: Integer;
    Y: Integer;
  end;
  PMyData = ^TMyData;

function Create(): PMyData; overload;
function Create( const X, Y: Integer ): PMyData; overload;
procedure Access( Data: PMyData; var X, Y: Integer );
procedure Modify( Data: PMyData; const X, Y: Integer );
procedure Destroy( Data: PMyData );

// TSearchFunc = function ( Data: Pointer ): Boolean;
function SearchFunc( Where, What: Pointer ): Boolean;
{
// TTouchFunc = procedure ( Data: Pointer );
procedure TouchFunc( Data: Pointer );
}
implementation

function Create(): PMyData;
var
  p: PMyData;
begin
  new( p );
  p^.X := 0;
  p^.Y := 0;
  Result := p;
end;

function Create( const X, Y: Integer ): PMyData;
var
  p: PMyData;
begin
  new( p );
  p^.X := X;
  p^.Y := Y;
  Result := p;
end;

procedure Access( Data: PMyData; var X, Y: Integer );
begin
  X := Data^.X;
  Y := Data^.Y;
end;

procedure Modify( Data: PMyData; const X, Y: Integer );
begin
  Data^.X := X;
  Data^.Y := Y;
end;

procedure Destroy( Data: PMyData );
begin
  if Assigned( Data ) then
  begin
    Dispose( Data );
    Data := nil;
  end;
end;

function SearchFunc( Where, What: Pointer ): Boolean;
begin
  if ( PMyData( Where )^.X = PMyData( What )^.X ) and ( PMyData( Where )^.Y = PMyData( What )^.Y ) then
    Result := true
  else
    Result := false;
end;
{
// TTouchFunc = procedure ( Data: Pointer );
procedure TouchFunc( Data: Pointer );
begin

end;
}
end.