Delphi Éè¼Æģʽ£º¡¶HeadFirstÉè¼Æģʽ¡·Delphi7´úÂë

ûÓÐÓ¦ÓÃ״̬ģʽµÄ´úÂë
1. ¹¤³ÌÎļþ
program Project1;
{$APPTYPE CONSOLE}
uses
uGumballMachine in 'uGumballMachine.pas';
var
aGumballMachine: TGumballMachine;
begin
aGumballMachine := TGumballMachine.Create(5);
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
Writeln;
aGumballMachine.InsertQuarter;
aGumballMachine.EjectQuarter;
aGumballMachine.TurnCrank;
Writeln;
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
aGumballMachine.EjectQuarter;
Writeln;
aGumballMachine.InsertQuarter;
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
aGumballMachine.InsertQuarter;
aGumballMachine.TurnCrank;
aGumballMachine.Free;
Readln;
end.
2.µ¥ÔªÎļþ
unit uGumballMachine;
interface
type
TGumballMachine = class(TObject)
private
FState: Integer;
FCount: Integer;
public
constructor Create(aCount: Integer);
procedure InsertQuarter;
procedure EjectQuarter;
procedure TurnCrank;
procedure Dispense;
end;
implementation
const
SOLD_OUT = 0;
NO_QUARTER = 1;
HAS_QUARTER = 2;
SOLD = 3;
{ TGumballMachine }
constructor TGumballMachine.Create(aCount: Integer);
begin
FCount := aCount;
FState := SOLD_OUT;
if FCount > 0 then
FState := NO_QUARTER;
end;
procedure TGumballMachine.Dispense;
begin
if FState = SOLD then
begin
Writeln('A gumball comes rolling out the slot');
FCount := FCount - 1;
if FCount = 0 then
begin
Writeln('Oops, out of Gumballs');
FState := SOLD_OUT;
end
else
FState := NO_QUARTER;
end;
if FState = NO_QUARTER then
Writeln('You need to pay first');
if FState = SOLD_OUT then
Writeln('No gumball dispensed');
if FState = HAS_QUARTER then
Writeln('No gumball dispensed');
end;
procedure TGumballMa