computer2.pas

简单计算器

unit COMPUTER2;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Buttons;

type
  TForm1 = class(TForm)
    SpeedButton1: TSpeedButton;
    SpeedButton2: TSpeedButton;
    SpeedButton3: TSpeedButton;
    SpeedButton4: TSpeedButton;
    SpeedButton5: TSpeedButton;
    SpeedButton6: TSpeedButton;
    SpeedButton7: TSpeedButton;
    SpeedButton8: TSpeedButton;
    SpeedButton9: TSpeedButton;
    SpeedButton10: TSpeedButton;
    SpeedButton11: TSpeedButton;
    SpeedButton12: TSpeedButton;
    SpeedButton13: TSpeedButton;
    SpeedButton14: TSpeedButton;
    SpeedButton15: TSpeedButton;
    SpeedButton16: TSpeedButton;
    SpeedButton17: TSpeedButton;
    SpeedButton18: TSpeedButton;
    Edit1: TEdit;
    procedure SpeedButton13Click(Sender: TObject);
    procedure SpeedButton9Click(Sender: TObject);
    procedure SpeedButton10Click(Sender: TObject);
    procedure SpeedButton11Click(Sender: TObject);
    procedure SpeedButton5Click(Sender: TObject);
    procedure SpeedButton6Click(Sender: TObject);
    procedure SpeedButton7Click(Sender: TObject);
    procedure SpeedButton1Click(Sender: TObject);
    procedure SpeedButton2Click(Sender: TObject);
    procedure SpeedButton3Click(Sender: TObject);
    procedure SpeedButton14Click(Sender: TObject);
    procedure SpeedButton8Click(Sender: TObject);
    procedure SpeedButton12Click(Sender: TObject);
    procedure SpeedButton16Click(Sender: TObject);
    procedure SpeedButton15Click(Sender: TObject);
    procedure SpeedButton4Click(Sender: TObject);
    procedure SpeedButton17Click(Sender: TObject);
    procedure SpeedButton18Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
   s1:string;
  r2:real;
  n :integer;

implementation

{$R *.dfm}

procedure TForm1.SpeedButton13Click(Sender: TObject);
begin
 edit1.Text:=edit1.Text+'0';
end;

procedure TForm1.SpeedButton9Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'1'; 
end;

procedure TForm1.SpeedButton10Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'2';
end;

procedure TForm1.SpeedButton11Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'3';
end;

procedure TForm1.SpeedButton5Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'4';
end;

procedure TForm1.SpeedButton6Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'5';
end;

procedure TForm1.SpeedButton7Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'6';
end;

procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'7';
end;

procedure TForm1.SpeedButton2Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'8';
end;

procedure TForm1.SpeedButton3Click(Sender: TObject);
begin
edit1.Text:=edit1.Text+'9';
end;

procedure TForm1.SpeedButton14Click(Sender: TObject);
begin
if edit1.text=''then edit1.text:='0.' else edit1.text:=edit1.text+'.';
end;

procedure TForm1.SpeedButton8Click(Sender: TObject);
begin
 n:=1;
s1:=edit1.Text;
edit1.Clear;
end;

procedure TForm1.SpeedButton12Click(Sender: TObject);
begin
 n:=2;
s1:=edit1.Text;
edit1.Clear;
end;

procedure TForm1.SpeedButton16Click(Sender: TObject);
begin
n:=3; 
s1:=edit1.Text;
edit1.Clear;
end;

procedure TForm1.SpeedButton15Click(Sender: TObject);
begin
n:=4; 
s1:=edit1.Text;
edit1.Clear;
end;

procedure TForm1.SpeedButton4Click(Sender: TObject);
begin
 if Edit1.Text = '' then
begin 
Exit;
end
else 
begin 
case n of 
1:r2:=strtofloat(s1)+strtofloat(edit1.Text);
2:r2:=strtofloat(s1)-strtofloat(edit1.Text);
3:r2:=strtofloat(s1)*strtofloat(edit1.Text);
4:if strtofloat(edit1.Text)=0 then
begin
edit1.clear;
edit1.Text:=edit1.Text+'0不能作为除数！';
exit;
end
else
r2:=strtofloat(s1)/strtofloat(edit1.Text);
end; 
edit1.Text:=floattostr(r2);
end;
end;

procedure TForm1.SpeedButton17Click(Sender: TObject);
begin
Form1.Close;
end;

procedure TForm1.SpeedButton18Click(Sender: TObject);
begin
 edit1.Clear;
end;

end.