数据库应用程序设计离线作业答案(9)

2013浙大远程教育

Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);

var

temp:string;

begin

if er then exit;

if pnt then

scr.Caption:=scr.Caption+(sender as Tbutton).Caption

else if (scr.Caption='0.') or fb then

begin

scr.Caption:=(sender as Tbutton).caption+'.';

fb:=false;

end

else

begin

temp:=scr.Caption;

insert((sender as Tbutton).Caption,temp,length(temp));

scr.Caption:=temp;

end;

end;

procedure TForm1.Button12Click(Sender: TObject);

var

temp:string;

begin

if er then exit;

if scr.Caption<>'0.' then

if pos('-',scr.Caption)>0 then

begin

temp:=scr.Caption;

delete(temp,1,1);

scr.Caption:=temp;

end

else

scr.Caption:='-'+scr.Caption;

end;

procedure TForm1.FormCreate(Sender: TObject);

begin

pnt:=false;

fstnm:=0;

fb:=false;

fbcaption:='';