delphi实现计算器

这篇文章是用delphi做了一个简单的计算器,代码如下:   unit Unit1;

interface

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

type
    TForm1 = class(TForm)
        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;
        Button17: TButton;
        procedure Button4Click(Sender: TObject);
        procedure Button1Click(Sender: TObject);
        procedure Button2Click(Sender: TObject);
        procedure Button3Click(Sender: TObject);
        procedure Button5Click(Sender: TObject);
        procedure Button6Click(Sender: TObject);
        procedure Button7Click(Sender: TObject);
        procedure Button9Click(Sender: TObject);
        procedure Button10Click(Sender: TObject);
        procedure Button11Click(Sender: TObject);
        procedure Button13Click(Sender: TObject);
        procedure Button8Click(Sender: TObject);
        procedure Button12Click(Sender: TObject);
        procedure Button15Click(Sender: TObject);
        procedure Button16Click(Sender: TObject);
        procedure Button17Click(Sender: TObject);
        procedure Button14Click(Sender: TObject);
    private
        { Private declarations }
    public
        { Public declarations }
    end;
type //自定义一个Tcompute的类

    Tcompute = object
    private //保护类中成员数据的安全

        temp1: double;
        temp2: double;
        temp3: double;
        sign: Char;

    public //把类中的成员函数进行共享


        function Add(x: double; y: double): Double;
        function Sub(x: double; y: double): Double;
        function Mult(x: double; y: double): Double;
        function Dived(x: double; y: double): Double;

    end;
var
    Form1: TForm1;
    Info: Tcompute; //声明Info是类Tcompute的对象


implementation

function Tcompute.Add(x: double; y: double): Double; //进行类的定义与实现

begin
    Result := x + y;
end;

function Tcompute.Sub(x: double; y: double): Double;
begin
    Result := x - y;
end;

function Tcompute.Mult(x: double; y: double): Double;
begin
    Result := x * y;
end;

function Tcompute.Dived(x: double; y: double): Double;
begin
if (y = 0) then
    begin
         Form1.Edit1.text:='1111111111';
        //ShowMessage('除数不能为0!'); //这里判断除数不能为0

        Result := x;
    end
    else
        Result := x / y;
end;

{$R *.dfm}

procedure TForm1.Button4Click(Sender: TObject);

begin
    Edit1.Clear;
    Info.temp1 := 0;
    Info.temp2 := 0;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
    Edit1.Text := Edit1.text + '7';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button2Click(Sender: TObject);

begin
    Edit1.Text := Edit1.text + '8';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button3Click(Sender: TObject);

begin
    Edit1.Text := Edit1.text + '9';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button5Click(Sender: TObject);

begin
    Edit1.Text := Edit1.text + '4';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button6Click(Sender: TObject);

begin
    Edit1.Text := Edit1.text + '5';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button7Click(Sender: TObject);

begin
    Edit1.Text := Edit1.text + '6';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button9Click(Sender: TObject);
begin
    Edit1.Text := Edit1.text + '1';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button10Click(Sender: TObject);
begin
    Edit1.Text := Edit1.text + '2';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button11Click(Sender: TObject);
begin
    Edit1.Text := Edit1.text + '3';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button13Click(Sender: TObject);
begin
    Edit1.Text := Edit1.text + '0';
    Info.temp1 := StrTofloat(Edit1.text);
end;

procedure TForm1.Button8Click(Sender: TObject);

begin
    Info.temp2 := Info.temp1;
    Info.sign := '+';
    Edit1.Clear;
end;

procedure TForm1.Button12Click(Sender: TObject);
begin

    Info.temp2 := Info.temp1;
    Info.sign := '-';
    Edit1.Clear;
end;

procedure TForm1.Button15Click(Sender: TObject);
begin

    Info.temp2 := Info.temp1;
    Info.sign := '*';
    Edit1.Clear;
end;

procedure TForm1.Button16Click(Sender: TObject);
begin
    Info.temp2 := Info.temp1;
    Info.sign := '/';
    Edit1.Clear;
end;

procedure TForm1.Button17Click(Sender: TObject);
begin

    if (Info.sign = '+') then
        Edit1.text := FloatToStr(Info.Add(Info.temp2, Info.temp1))
    else
        if (Info.sign = '-') then
            Edit1.text := FloatToStr(Info.Sub(Info.temp2, Info.temp1))
        else
            if (Info.sign = '*') then
                Edit1.text := FloatToStr(Info.Mult(Info.temp2, Info.temp1))
            else
                if (Info.sign = '/') then
                    Edit1.text := FloatToStr(Info.Dived(Info.temp2, Info.temp1));
    Info.temp1 := StrToFloat(Edit1.Text);

end;

procedure TForm1.Button14Click(Sender: TObject);
begin

    Edit1.Text := Edit1.Text + '.';
    Info.temp1 := StrToFloat(Edit1.Text);

end;

end.    

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