简单计算器交作业

kamalo

大神莫笑我

简单计算器

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    SpeedButton1: TSpeedButton;     //计算器上有16个按钮
    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;
    procedure FormCreate(Sender: TObject);
    procedure SpeedButton1Click(Sender: TObject);
    procedure SpeedButton2Click(Sender: TObject);
    procedure SpeedButton3Click(Sender: TObject);
    procedure SpeedButton4Click(Sender: TObject);
    procedure SpeedButton7Click(Sender: TObject);
    procedure SpeedButton8Click(Sender: TObject);
    procedure SpeedButton9Click(Sender: TObject);
    procedure SpeedButton13Click(Sender: TObject);
    procedure SpeedButton14Click(Sender: TObject);
    procedure SpeedButton15Click(Sender: TObject);
    procedure SpeedButton5Click(Sender: TObject);
    procedure SpeedButton6Click(Sender: TObject);
    procedure SpeedButton10Click(Sender: TObject);
    procedure SpeedButton11Click(Sender: TObject);
    procedure SpeedButton12Click(Sender: TObject);
    procedure SpeedButton16Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  temp1:string;     //存储第一次Edit1中的字符串
  temp2:real;      //计算结果为实数
  flag:integer;     //用于加减乘除在case中的条件

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  Edit1.Text:=''；     //清空Edit1
end;

procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '1';     //可以多次向Edit1中填入1
end;

procedure TForm1.SpeedButton2Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '2';     //可以多次向Edit1中填入2
end;

procedure TForm1.SpeedButton3Click(Sender: TObject);
begin
   Edit1.Text:= Edit1.Text + '3';
end;

procedure TForm1.SpeedButton4Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '0';
end;

procedure TForm1.SpeedButton7Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '4';
end;

procedure TForm1.SpeedButton8Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '5';
end;

procedure TForm1.SpeedButton9Click(Sender: TObject);
begin
  Edit1.Text:= Edit1.Text + '6';
end;

procedure TForm1.SpeedButton13Click(Sender: TObject);
begin
   Edit1.Text:= Edit1.Text + '7';
end;

procedure TForm1.SpeedButton14Click(Sender: TObject);
begin
   Edit1.Text:= Edit1.Text + '8';
end;

procedure TForm1.SpeedButton15Click(Sender: TObject);
begin
   Edit1.Text:= Edit1.Text + '9';
end;

procedure TForm1.SpeedButton5Click(Sender: TObject);
begin
  flag:= 1;     //加法在case条件中设为1
  temp1:=Edit1.Text;     //将第一次输入的字符串存储在变量temp1中
  Edit1.Text:='';
end;

procedure TForm1.SpeedButton6Click(Sender: TObject);
begin
  flag:= 2;       //减法在case条件中设为2
  temp1:=Edit1.Text;
  Edit1.Text:='';
end;

procedure TForm1.SpeedButton10Click(Sender: TObject);
begin
  flag:= 3;
  temp1:=Edit1.Text;
  Edit1.Text:='';
end;

procedure TForm1.SpeedButton11Click(Sender: TObject);
begin
  flag:= 4;
  temp1:=Edit1.Text;
  Edit1.Text:='';
end;

procedure TForm1.SpeedButton12Click(Sender: TObject);
begin
  case flag of
  1: temp2:=strtofloat(Edit1.Text) + strtofloat(temp1);     //分别计算加减乘除，结果赋值给实数变量temp2
  2: temp2:=strtofloat(temp1) - strtofloat(Edit1.Text);
  3: temp2:=strtofloat(Edit1.Text) * strtofloat(temp1);
  4: temp2:=strtofloat(temp1) / strtofloat(Edit1.Text);

end;
edit1.Text:=floattostr(temp2);     //将计算所得结果实数变量temp2变成字符串赋值给Edit1
end;
procedure TForm1.SpeedButton16Click(Sender: TObject);
begin
  Edit1.Text:='';     //实现复位按钮功能
end;

end.

lsx116

零分

小人鱼

新人表示看不懂

kamalo

主要有16个按钮, 分别实现按钮0~9, 加减乘除过程在等于按钮中实现,  用到了case循环, 因为Edit1中输入的是字符串, 而计算中需要变成实数, 计算结果temp2是实数要变成字符串才能赋值给Edit1

hynw0000

1