数据库应用程序设计离线作业答案(10)

2013浙大远程教育

er:=false;

end;

procedure TForm1.Button11Click(Sender: TObject);

begin

if er then exit;

pnt:=true;

end;

procedure TForm1.Button13Click(Sender: TObject);

begin

if er then exit;

if not fb then

button20click(nil);

if er then exit;

fstnm:=strtofloat(scr.Caption);

fbcaption:=(sender as Tbutton).Caption;

fb:=true;

pnt:=false;

end;

procedure TForm1.Button20Click(Sender: TObject);

begin

if er then exit;

if fbcaption='+' then

begin

scr.Caption:=floattostr(strtofloat(scr.Caption)+fstnm);

end;

if fbcaption='-' then

begin

scr.Caption:=floattostr(fstnm-strtofloat(scr.Caption));

end;

if fbcaption='*' then

begin

scr.Caption:=floattostr(strtofloat(scr.Caption)*fstnm);

end;

if fbcaption='/' then

begin

if scr.Caption<>'0.' then

scr.Caption:=floattostr(fstnm/strtofloat(scr.Caption))

else

begin

scr.Caption:='zero divid error!';

er:=true;

end;

end;