命令模式：将一个请求封装为一个对象，从而你可用不同的请求对客户进行参数化；对请求排队或记录请求日志，以及支持可撤销操作。 命令类： 1.命令角色：声明了一个给所有具体命令类的抽象接口。这是一个抽象角色。 2.具体命令角色：定义一个接受者和行为之间的弱耦合；实现execute方法，负责调用接受的相应操作。execute()方法通常叫做执行方法 3.客户角色：创建一个具体命令对象并确定其接受者。 4.请求者角色：负责调用命令对象执行请求，相关的方法叫做行动方法。 5.接受者角色：负责具体实施和执行一个请求。 作用： 1.抽象出待执行的动作以参数化对象。 2.在不同的时刻指定、排列和执行请求。 3.支持取消操作 4.支持修改日志
<?<span php><span><span>
<span interface><span command><span public> <span function><span execute><span><span>
<span class> ConcreteCommand <span implements><span command><span private> <span><span><span public> <span function> __construct(<span><span><span>->_receiver = <span><span><span public> <span function><span execute><span>->_receiver-><span action><span><span>
<span class><span receiver><span private> <span><span><span public> <span function> __construct(<span><span><span>->_name = <span><span><span><span>
<span public> <span function><span action><span echo> <span>->_name.'do action .<br/>'<span><span><span>
<span class><span invoker><span private> <span><span><span public> <span function> __construct(<span><span><span>->_command = <span><span><span public> <span function><span action><span>->_command-><span execute><span><span>
<span class><span client><span public> <span static> <span function><span main><span> = <span new> Receiver('jaky'<span><span> = <span new> ConcreteeCommand(<span><span><span> = <span new> Invoker(<span><span><span>-><span action client>::<span main>?></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
