Delphi 设计模式：《HeadFirst设计模式》Delphi7代码---命令模式之RemoteControlTest

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djCode

最新推荐文章于 2025-08-10 08:32:47 发布

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文章标签： delphi 设计模式 constructor integer class string

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本文介绍了一种软件设计模式——命令模式的应用实例。通过定义命令接口并创建具体命令类来封装请求，实现了命令发送者与接收者之间的解耦。文章展示了如何使用Delphi 7.0实现命令模式，包括命令接收者、命令对象及命令请求者的具体实现。

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1. 命令的接收者

{《HeadFirst设计模式》之命令模式 } { 本单元中的类为命令的接收者 } { 编译工具：Delphi7.0 } { 联系方式：xshlife@163.com } unit uReceiveObject; interface type TLight = class(TObject) private FLocation: String; public constructor Create(aLocation: String); procedure Open; procedure Off; end; TCeilingFan = class(TObject) private FLevel : Integer; FLocation: String; function GetSpeed: Integer; public constructor Create(aLocation: String); procedure High; procedure Medium; procedure Low; procedure Off; property Speed: Integer read GetSpeed; end; TGarageDoor = class(TObject) private FLocation: String; public constructor Create(aLocation: String); procedure Up; procedure Down; procedure Stop; procedure LightOn; procedure LightOff; end; TStereo = class(TObject) private FLocation: String; public constructor Create(aLocation: String); procedure Play; procedure Off; procedure SetCD; procedure SetDVD; procedure SetRadio; procedure SetVolume(aVolume: Integer); end; TTV = class(TObject) private FLocation: String; FChannel : Integer; public constructor Create(aLocation: String); procedure Open; procedure Off; procedure SetInputChannel; end; THottub = class(TObject) private FOpen: Boolean; FTemp: Integer; function GetTemp: Integer; procedure SetTemp(const Value: Integer); public function Open: Boolean; function Off : Boolean; procedure BubblesOpen; procedure BubblesOff; procedure JetsOpen; procedure JetsOff; procedure Heat; procedure Cool; property Temp: Integer read GetTemp write SetTemp; end; implementation const SPEED_HIGH = 2; SPEED_MEDIUM = 1; SPEED_LOW = 0; { TLight } constructor TLight.Create(aLocation: String); begin FLocation := aLocation; end; procedure TLight.Off; begin Writeln(FLocation + 'Light is off.'); end; procedure TLight.Open; begin Writeln(FLocation + 'Light is on.'); end; { TCeilingFan } constructor TCeilingFan.Create(aLocation: String); begin FLocation := aLocation; end; function TCeilingFan.GetSpeed: Integer; begin Result := FLevel; end; procedure TCeilingFan.High; begin FLevel := SPEED_HIGH; Writeln(FLocation + 'Ceiling fan is on high.'); end; procedure TCeilingFan.Low; begin FLevel := SPEED_LOW; Writeln(FLocation + 'Ceiling fan is on low.'); end; procedure TCeilingFan.Medium; begin FLevel := SPEED_MEDIUM; Writeln(FLocation + 'Ceiling fan is on medium.'); end; procedure TCeilingFan.Off; begin FLevel := 0; Writeln(FLocation + 'Ceiling fan is on off.'); end; { TGarageDoor } constructor TGarageDoor.Create(aLocation: String); begin FLocation := aLocation; end; procedure TGarageDoor.Down; begin Writeln(FLocation + 'Garage door is down.'); end; procedure TGarageDoor.LightOff; begin Writeln(FLocation + 'Garage light is off.'); end; procedure TGarageDoor.LightOn; begin Writeln(FLocation + 'Garage light is on.'); end; procedure TGarageDoor.Stop; begin Writeln(FLocation + 'Garage door is stopped.'); end; procedure TGarageDoor.Up; begin Writeln(FLocation + 'Garage door is up.'); end; { TStereo } constructor TStereo.Create(aLocation: String); begin FLocation := aLocation; end; procedure TStereo.Off; begin Writeln(FLocation + 'Stereo is off.'); end; procedure TStereo.Play; begin Writeln(FLocation + 'Stereo is on.'); end; procedure TStereo.SetCD; begin Writeln(FLocation + 'Stereo is set for CD input.'); end; procedure TStereo.SetDVD; begin Writeln(FLocation + 'Stereo is set for DVD input.'); end; procedure TStereo.SetRadio; begin Writeln(FLocation + 'Stereo is set for radio.'); end; procedure TStereo.SetVolume(aVolume: Integer); begin Writeln(FLocation + 'Stereo volume set to ', aVolume); end; { TTV } constructor TTV.Create(aLocation: String); begin FLocation := aLocation; end; procedure TTV.Off; begin Writeln(FLocation + 'TV is off.'); end; procedure TTV.Open; begin Writeln(FLocation + 'TV is on.'); end; procedure TTV.SetInputChannel; begin FChannel := 3; Writeln('Channel is set for VCR.'); end; { THottub } procedure THottub.BubblesOff; begin if Off then Writeln('Hottub is not bubbling.'); end; procedure THottub.BubblesOpen; begin if Open then Writeln('Hottub is bubbling.'); end; procedure THottub.Cool; begin FTemp := 98; Writeln('Hottub is cooling to 98 degrees.'); end; function THottub.GetTemp: Integer; begin Result := FTemp; end; procedure THottub.Heat; begin FTemp := 105; Writeln('Hottub is heating to a steaming 105 degrees.'); end; procedure THottub.JetsOff; begin if Off then Writeln('Hottub jets are off.'); end; procedure THottub.JetsOpen; begin if Open then Writeln('Hottub jets are open.'); end; function THottub.Off: Boolean; begin FOpen := False; Result := FOpen; end; function THottub.Open: Boolean; begin FOpen := True; Result := FOpen; end; procedure THottub.SetTemp(const Value: Integer); begin FTemp := Value; end; end.

2. 命令对象

{《HeadFirst设计模式》之命令模式 } { 将命令接收者中的动作包装成命令对象 } { 编译工具：Delphi7.0 } { 联系方式：xshlife@163.com } unit uCommandObject; interface uses uReceiveObject; type TCommand = class(TObject) public procedure Execute; virtual; abstract; end; TNoCommand = class(TCommand) public procedure Execute; override; end; TLightOnCommand = class(TCommand) private FLight: TLight; public constructor Create(aLight: TLight); procedure Execute; override; end; TLightOffCommand = class(TCommand) protected FLight: TLight; public constructor Create(aLight: TLight); procedure Execute; override; end; TLivingRoomLightOnCommand = class(TLightOnCommand) end; TLivingRoomLightOffCommand = class(TLightOffCommand) end; TKitchenLightOnCommand = class(TLightOnCommand) end; TKitchenLightOffCommand = class(TLightOffCommand) end; TCeilingFanOnCommand = class(TCommand) private FCeilingFan: TCeilingFan; public constructor Create(aCeilingFan: TCeilingFan); procedure Execute; override; end; TCeilingFanOffCommand = class(TCommand) private FCeilingFan: TCeilingFan; public constructor Create(aCeilingFan: TCeilingFan); procedure Execute; override; end; TGarageDoorUpCommand = class(TCommand) private FGarageDoor: TGarageDoor; public constructor Create(aGarageDoor: TGarageDoor); procedure Execute; override; end; TGarageDoorDownCommand = class(TCommand) private FGarageDoor: TGarageDoor; public constructor Create(aGarageDoor: TGarageDoor); procedure Execute; override; end; TStereoOnWithCDCommand = class(TCommand) private FStereo: TStereo; public constructor Create(aStereo: TStereo); procedure Execute; override; end; TStereoOffCommand = class(TCommand) private FStereo: TStereo; public constructor Create(aStereo: TStereo); procedure Execute; override; end; THottubOnCommand = class(TCommand) private FHottub: THottub; public constructor Create(aHottub: THottub); procedure Execute; override; end; THottubOffCommand = class(TCommand) private FHottub: THottub; public constructor Create(aHottub: THottub); procedure Execute; override; end; implementation { TNoCommand } procedure TNoCommand.Execute; begin end; { TLightOnCommand } constructor TLightOnCommand.Create(aLight: TLight); begin FLight := aLight; end; procedure TLightOnCommand.Execute; begin FLight.Open; end; { TLightOffCommand } constructor TLightOffCommand.Create(aLight: TLight); begin FLight := aLight; end; procedure TLightOffCommand.Execute; begin FLight.Off; end; { TLivingRoomLightOnCommand } { TLivingRoomLightOffCommand } { TKitchenLightOnCommand } { TKitchenLightOffCommand } { TCeilingFanOnCommand } constructor TCeilingFanOnCommand.Create(aCeilingFan: TCeilingFan); begin FCeilingFan := aCeilingFan; end; procedure TCeilingFanOnCommand.Execute; begin FCeilingFan.High; end; { TCeilingFanOffCommand } constructor TCeilingFanOffCommand.Create(aCeilingFan: TCeilingFan); begin FCeilingFan := aCeilingFan; end; procedure TCeilingFanOffCommand.Execute; begin FCeilingFan.Off; end; { TGarageDoorUpCommand } constructor TGarageDoorUpCommand.Create(aGarageDoor: TGarageDoor); begin FGarageDoor := aGarageDoor; end; procedure TGarageDoorUpCommand.Execute; begin FGarageDoor.Up; FGarageDoor.LightOn; end; { TGarageDoorDownCommand } constructor TGarageDoorDownCommand.Create(aGarageDoor: TGarageDoor); begin FGarageDoor := aGarageDoor; end; procedure TGarageDoorDownCommand.Execute; begin FGarageDoor.Down; FGarageDoor.LightOff; end; { TStereoOnWithCDCommand } constructor TStereoOnWithCDCommand.Create(aStereo: TStereo); begin FStereo := aStereo; end; procedure TStereoOnWithCDCommand.Execute; begin FStereo.Play; FStereo.SetCD; FStereo.SetVolume(11); end; { TStereoOffCommand } constructor TStereoOffCommand.Create(aStereo: TStereo); begin FStereo := aStereo; end; procedure TStereoOffCommand.Execute; begin FStereo.Off; end; { THottubOnCommand } constructor THottubOnCommand.Create(aHottub: Thottub); begin FHottub := aHottub; end; procedure THottubOnCommand.Execute; begin FHottub.Open; FHottub.Heat; FHottub.BubblesOpen; FHottub.JetsOpen; end; { THottubOffCommand } constructor THottubOffCommand.Create(aHottub: THottub); begin FHottub := aHottub; end; procedure THottubOffCommand.Execute; begin FHottub.Cool; FHottub.Off; end; end.

3. 命令的请求者

{《HeadFirst设计模式》之命令模式 } { 本单元中的类为命令的请求者，向命令对象发出请求，} { 命令对象通过委托，执行命令接收者中的动作。 } { 编译工具：Delphi7.0 } { 联系方式：xshlife@163.com } unit uInvoker; interface uses uCommandObject; type TRemoteControl = class(TObject) private FOnCommands : array of TCommand; FOffCommands: array of TCommand; FNoCommand : TCommand; public constructor Create; destructor Destroy; override; procedure SetCommand(aSlot: Integer; aOnCommand, aOffCommand: TCommand); procedure OnButtonWasPressed(aSlot: Integer); procedure OffButtonWasPressed(aSlot: Integer); end; implementation { TRemoteControl } constructor TRemoteControl.Create; var i: Integer; begin SetLength(FOnCommands, 7); SetLength(FOffCommands, 7); FNoCommand := TNoCommand.Create; for i := 0 to 6 do begin FOnCommands [i] := FNoCommand; FOffCommands[i] := FNoCommand; end; end; destructor TRemoteControl.Destroy; begin FNoCommand.Free; inherited; end; procedure TRemoteControl.OffButtonWasPressed(aSlot: Integer); begin FOffCommands[aSlot].Execute; end; procedure TRemoteControl.OnButtonWasPressed(aSlot: Integer); begin FOnCommands [aSlot].Execute; end; procedure TRemoteControl.SetCommand(aSlot: Integer; aOnCommand, aOffCommand: TCommand); begin FOnCommands [aSlot] := aOnCommand; FOffCommands[aSlot] := aOffCommand; end; end.

4. 客户端,创建具体的命令对象

{《HeadFirst设计模式》之命令模式 } { 客户端负责创建具体的命令对象 } { 编译工具：Delphi7.0 } { 联系方式：xshlife@163.com } program pRemoteControlTest; {$APPTYPE CONSOLE} uses uReceiveObject in 'uReceiveObject.pas', uCommandObject in 'uCommandObject.pas', uInvoker in 'uInvoker.pas'; var RemoteControl : TRemoteControl; LivingRoomLight: TLight; KitchenLight : TLight; CeilingFan : TCeilingFan; GarageDoor : TGarageDoor; Stereo : TStereo; LivingRoomLightOnCommand : TLightOnCommand; LivingRoomLightOffCommand: TLightOffCommand; KitchenLightOnCommand : TLightOnCommand; KitchenLightOffCommand : TLightOffCommand; CeilingFanOnCommand : TCeilingFanOnCommand; CeilingFanOffCommand : TCeilingFanOffCommand; GarageDoorUpCommand : TGarageDoorUpCommand; GarageDoorDownCommand : TGarageDoorDownCommand; StereoOnWithCDCommand : TStereoOnWithCDCommand; StereoOffCommand : TStereoOffCommand; begin RemoteControl := TRemoteControl.Create; LivingRoomLight := TLight.Create('Living Room'); KitchenLight := TLight.Create('Kitchen'); CeilingFan := TCeilingFan.Create('Living Room '); GarageDoor := TGarageDoor.Create('');; Stereo := TStereo.Create('Living Room'); LivingRoomLightOnCommand := TLightOnCommand.Create(LivingRoomLight); LivingRoomLightOffCommand := TLightOffCommand.Create(LivingRoomLight); KitchenLightOnCommand := TLightOnCommand.Create(KitchenLight); KitchenLightOffCommand := TLightOffCommand.Create(KitchenLight); CeilingFanOnCommand := TCeilingFanOnCommand.Create(CeilingFan); CeilingFanOffCommand := TCeilingFanOffCommand.Create(CeilingFan); GarageDoorUpCommand := TGarageDoorUpCommand.Create(GarageDoor); GarageDoorDownCommand := TGarageDoorDownCommand.Create(GarageDoor); StereoOnWithCDCommand := TStereoOnWithCDCommand.Create(Stereo); StereoOffCommand := TStereoOffCommand.Create(Stereo); RemoteControl.SetCommand(0, LivingRoomLightOnCommand, LivingRoomLightOffCommand); RemoteControl.SetCommand(1, KitchenLightOnCommand, KitchenLightOffCommand); RemoteControl.SetCommand(2, CeilingFanOnCommand, CeilingFanOffCommand); RemoteControl.SetCommand(3, StereoOnWithCDCommand, StereoOffCommand); RemoteControl.SetCommand(4, GarageDoorUpCommand, GarageDoorDownCommand); RemoteControl.OnButtonWasPressed (0); RemoteControl.OffButtonWasPressed(0); RemoteControl.OnButtonWasPressed (1); RemoteControl.OffButtonWasPressed(1); RemoteControl.OnButtonWasPressed (2); RemoteControl.OffButtonWasPressed(2); RemoteControl.OnButtonWasPressed (3); RemoteControl.OffButtonWasPressed(3); RemoteControl.OnButtonWasPressed (4); RemoteControl.OffButtonWasPressed(4); RemoteControl.Free; LivingRoomLight.Free; KitchenLight.Free; CeilingFan.Free; GarageDoor.Free; Stereo.Free; LivingRoomLightOnCommand.Free; LivingRoomLightOffCommand.Free; KitchenLightOnCommand.Free; KitchenLightOffCommand.Free; CeilingFanOnCommand.Free; CeilingFanOffCommand.Free; GarageDoorUpCommand.Free; GarageDoorDownCommand.Free; StereoOnWithCDCommand.Free; StereoOffCommand.Free; Readln; end.

运行结果：