Delphi 之运算符重载
Delphi 7之后的版本,增加了运算符的重载。虽然不尽人意(需要写特定英文),但有总比没有强。
例:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
T3DPoint = record
X, Y, Z: Double;
class operator ADD(ALeftPoint, ARightPoint: T3DPoint): T3DPoint; {重载'+'运算符}
end;
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
{ T3DPoint }
class operator T3DPoint.ADD(ALeftPoint, ARightPoint: T3DPoint): T3DPoint;
begin
Result.X := ALeftPoint.X + ARightPoint.X;
Result.Y := ALeftPoint.Y + ARightPoint.Y;
Result.Z := ALeftPoint.Z + ARightPoint.Z;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
A, B, Z: T3DPoint;
begin
A.X := 1; A.Y := 1; A.Z := 1;
B.X := 3; B.Y := 3; B.Z := 3;
Z := A + B;
ShowMessageFmt('%f, %f, %f', [Z.X, Z.Y, Z.Z]); {4.00, 4.00, 4.00}
//ShowMessage(FloatToStr(Z.X) + ',' + FloatToStr(Z.Y) + ',' + FloatToStr(Z.Z)); {4, 4, 4}
end;
end.
下面附上所有的运算符:
重载特定英文 行为(或目数) 方法 &nbs
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总结如下:
Unit Unit1;
Interface
Uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
Type
TForm1 = Class(TForm)
Button1: TButton; ......