computer.~pas

delphi renyuanguanlixinxioxitong

unit computer;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Button5: TButton;
    Button6: TButton;
    Button7: TButton;
    Button8: TButton;
    Button9: TButton;
    Button10: TButton;
    Button11: TButton;
    Button12: TButton;
    Button13: TButton;
    Button14: TButton;
    Button15: TButton;
    Button16: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure Button5Click(Sender: TObject);
    procedure Button6Click(Sender: TObject);
    procedure Button7Click(Sender: TObject);
    procedure Button8Click(Sender: TObject);
    procedure Button9Click(Sender: TObject);
    procedure Button10Click(Sender: TObject);
    procedure Button11Click(Sender: TObject);
    procedure Button12Click(Sender: TObject);
    procedure Button13Click(Sender: TObject);
    procedure Button14Click(Sender: TObject);
    procedure Button15Click(Sender: TObject);
    procedure Button16Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
var
  temp1:string;
  temp2:real;
  n:integer;

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
   edit1.Text:=edit1.Text+'1';  //在计算框中输入数字"1"
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'2';  //在计算框中输入数字"2"
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'3';  //在计算框中输入数字"3"
end;

procedure TForm1.Button4Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'4';  //在计算框中输入数字"4"
end;

procedure TForm1.Button5Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'5';  //在计算框中输入数字"5"
end;

procedure TForm1.Button6Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'6';  //在计算框中输入数字"6"
end;

procedure TForm1.Button7Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'7';  //在计算框中输入数字"7"
end;

procedure TForm1.Button8Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'8';  //在计算框中输入数字"8"
end;

procedure TForm1.Button9Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'9';  //在计算框中输入数字"9"
end;

procedure TForm1.Button10Click(Sender: TObject);
begin
  edit1.Text:=edit1.Text+'0';  //在计算框中输入数字"0"
end;

procedure TForm1.Button11Click(Sender: TObject);
begin
  n:=1; //为加法运算设置标志变量
  temp1:=edit1.text; //为临时变量temp1赋值
  edit1.clear; //清空运算框  
end;

procedure TForm1.Button12Click(Sender: TObject);
begin
  n:=2; //为减法运算设置标志变量
  temp1:=edit1.text; //为临时变量temp1赋值
  edit1.clear; //清空运算框

end;

procedure TForm1.Button13Click(Sender: TObject);
begin
  n:=3; //为乘法运算设置标志变量
  temp1:=edit1.text; //为临时变量temp1赋值
  edit1.clear; //清空运算框
end;

procedure TForm1.Button14Click(Sender: TObject);
begin
  n:=4; //为除法运算设置标志变量
  temp1:=edit1.text; //为临时变量temp1赋值
  edit1.clear; //清空运算框
end;

procedure TForm1.Button15Click(Sender: TObject);
begin
  edit1.Clear; //清除文本框中的数字
end;

procedure TForm1.Button16Click(Sender: TObject);
begin
  case n of
     1:temp2:=strtofloat(temp1)+strtofloat(edit1.text);
     2:temp2:=strtofloat(temp1)-strtofloat(edit1.text);
     3:temp2:=strtofloat(edit1.text)*strtofloat(temp1);
     4:if strtofloat(edit1.text)=0 then
       begin
         application.MessageBox ('除数为0！','错误');
         exit;
       end
       else
         temp2:=strtofloat(temp1)/strtofloat(edit1.text);
       end;
  edit1.text:=floattostr(temp2);
end;

end.