Positive Zahlen in negative umwandeln

[Sir Rufo]

Ja so geht das aber nicht, das ist ja gar nicht Thread-Safe ...

Zitat von mr_emre_d:

Also lieber Larsi

Hier ne nützliche Klasse, die diese Superfunktion beinhaltet

Code:

interface

type
  TNeg = Class
  private
    FNumber: pInteger;
    procedure SetNumber(const Value: pInteger);
  public
    constructor Create(var Number: Integer );
    property Number: pInteger Read FNumber Write SetNumber;
    procedure Neg;
  End;

implementation

constructor TNeg.Create(var Number: Integer );
begin
  FNumber := @Number;
  Neg;
  Free;
end;

procedure TNeg.Neg;
begin
  Number^ := -Round(((sqrt(Power(Number^, 2)) * (-6)) / 6) - 2*Succ(Number^ xor
    (1 shl Pred(SizeOf(Integer) shl 3) + MAXINT)) );
end;

procedure TNeg.SetNumber(const Value: pInteger);
begin
  FNumber := Value;
end;

Und so kann sie verwendet werden:

Code:

var X: IntegeR;
begin
  X:= 10;
  TNeg.Create(X);
  ShowMessage( IntToStr( x ) );
end;

EDIT:
Credits go to DeddyH & Melfin
Thanks for ur help

So kann er das in allen Lebenslagen verwenden ...

Code:

interface

type
  TNeg = Class
  private
    FCS : TCriticalSection;
    FNumber: pInteger;
    function GetNumber : pInteger;
    procedure SetNumber(const Value: pInteger);
  public
    constructor Create(var Number: Integer );
    property Number: pInteger Read GetNumber Write SetNumber;
    procedure Neg;
  End;

implementation

constructor TNeg.Create(var Number: Integer );
begin
  FCS := TCriticalSection.Create;
  FNumber := @Number;
  Neg;
  Free;
end;

procedure TNeg.Neg;
begin
  Number^ := -Round(((sqrt(Power(Number^, 2)) * (-6)) / 6) - 2*Succ(Number^ xor
    (1 shl Pred(SizeOf(Integer) shl 3) + MAXINT)) );
end;

function TNeg.GetNumber : pInteger;
begin
  FCS.Enter;
  try
    RESULT := FNumber;
  finally
    FCS.Leave;
  end;
end;

procedure TNeg.SetNumber(const Value: pInteger);
begin
  FCS.Enter;
  try
    FNumber := Value;
  finally
    FCS.Leave;
  end;
end;

cu

Oliver

P.S.: Hat einer den Larsi schon mal wieder gesehen ...