命令模式
延迟任务的例子：
public class WakeUpCommand : ICommand { public bool executed = false; //这里开关可以控制自己的逻辑块，但是这里暂时是个摆设 public void Execute() { Trace.WriteLine("working..."); executed = true; } } public class SleepCommand : ICommand { private ICommand wakeUpCommand = null; //唤醒命令 private ActiveObjectEngine engine = null; //命令集 private DateTime startTime; //开始执行时间标记 private long sleepTime = 0; //休眠时间戳 private bool started = false; public SleepCommand(ICommand wakeUpCommand, ActiveObjectEngine engine, long sleepTime) { this.wakeUpCommand = wakeUpCommand; this.engine = engine; this.sleepTime = sleepTime; } public void Execute() { DateTime currentTime = DateTime.Now; if (!started) { started = true; startTime = currentTime; engine.Add(this); } else { if (currentTime.Subtract(startTime).TotalMilliseconds < sleepTime) { engine.Add(this); } else { engine.Add(wakeUpCommand); } } } } public class ActiveObjectEngine { private List<ICommand> commands = new List<ICommand>(); public void Run() { while (commands.Count > 0) { var command = commands[0]; commands.RemoveAt(0); command.Execute(); } } public void Add(ICommand command) { commands.Add(command); } } public interface ICommand { void Execute(); } public class DelayTyper : ICommand { private long itsDelay; private char itsChar; private static bool stop = false; private static ActiveObjectEngine engine = new ActiveObjectEngine(); private class StopCommand : ICommand { public void Execute() { DelayTyper.stop = true; } } public static void FakeMain(params string[] args) { engine.Add(new DelayTyper(100, '1')); engine.Add(new DelayTyper(300, '3')); engine.Add(new DelayTyper(500, '5')); engine.Add(new DelayTyper(700, '7')); ICommand stopCommand = new StopCommand(); engine.Add(new SleepCommand(stopCommand, engine, 20000)); engine.Run(); } public void Execute() { Trace.Write(itsChar); if (!stop) DelayAndRepeat(); } private void DelayAndRepeat() { engine.Add(new SleepCommand(this, engine, itsDelay)); } public DelayTyper(long itsDelay, char itsChar) { this.itsDelay = itsDelay; this.itsChar = itsChar; } }
实现：
[Test] public void TestSleepC() { #region test001 WakeUpCommand wakeUpCommand = new WakeUpCommand(); ActiveObjectEngine activeObjectEngine = new ActiveObjectEngine(); SleepCommand sleepCommand = new SleepCommand(wakeUpCommand, activeObjectEngine, 10000);//10秒 activeObjectEngine.Add(sleepCommand); DateTime start = DateTime.Now; activeObjectEngine.Run(); DateTime end = DateTime.Now; Trace.WriteLine($"第一次休眠:{start.Subtract(end)}"); sleepCommand = new SleepCommand(wakeUpCommand, activeObjectEngine, 100); activeObjectEngine.Add(sleepCommand); start = DateTime.Now; activeObjectEngine.Run(); end = DateTime.Now; Trace.WriteLine($"第二次休眠:{start.Subtract(end)}"); activeObjectEngine.Add(sleepCommand); start = DateTime.Now; activeObjectEngine.Run(); //执行sleep else分支 end = DateTime.Now; Trace.WriteLine($"第三次休眠:{start.Subtract(end)}"); #endregion } [Test] public void TestDelayTyper() { DelayTyper.FakeMain(); }
计算器例子：
public class Command : ICommand { private Queue<decimal> queue = new Queue<decimal>(); public decimal[] GetResults=>queue.ToArray(); private Receiver _receiver; public Receiver Receiver { get => _receiver; set => _receiver=value; } public decimal Execute(params decimal[] items) { var result = _receiver.Cal(items); queue.Enqueue(result); return result; } public decimal Reset() { return queue.Dequeue(); } } public class Add : Receiver { public decimal Cal(params decimal[] items) { return items.Aggregate((x, y) => x + y); } } public class Sub : Receiver { public decimal Cal(params decimal[] items) { return items.Aggregate((x, y) => x - y); } } public class Mul : Receiver { public decimal Cal(params decimal[] items) { return items.Aggregate((x, y) => x * y); } } public class Div : Receiver { public decimal Cal(params decimal[] items) { return items.Aggregate((x, y) => x/ y); } } public interface Receiver { decimal Cal(params decimal[] items); } public interface ICommand { decimal Execute(params decimal[] items);
decimal Reset();
Receiver Receiver { get; set; } }
客户端实现：
ICommand addCommand = new Command(); addCommand.Receiver = new Add(); ICommand subCommand = new Command(); subCommand.Receiver = new Sub();
下面是另外示例：
public class Store { private readonly Dictionary<string, Func<decimal[], decimal>> _dic = new Dictionary<string, Func<decimal[], decimal>>() { {"add",items=>items.Aggregate((x,y)=>x+y) }, {"sub",items=>items.Aggregate((x,y)=>x-y) }, {"mul",items=>items.Aggregate((x,y)=>x*y) }, {"div",items=>items.Aggregate((x,y)=>x/y) } }; private readonly Dictionary<string, decimal[]> _parameters = new Dictionary<string, decimal[]>(); public decimal GetAddResult() { return GetResult("add"); } public decimal GetSubResult() { return GetResult("sub"); } public decimal GetMulResult() { return GetResult("mul"); } public decimal GetDivResult() { return GetResult("div"); } public void Add(params decimal[] items) { var key = $"add_{Guid.NewGuid().ToString()}"; _parameters.Add(key, items.ToArray()); } public void RestAdd() { Remove("add"); } public void Sub(params decimal[] items) { var key = $"sub{Guid.NewGuid().ToString()}"; _parameters.Add(key, items.ToArray()); } public void RestSub() { Remove("sub"); } public void Mul(params decimal[] items) { var key = $"mul_{Guid.NewGuid().ToString()}"; _parameters.Add(key, items.ToArray()); } public void RestMul() { Remove("mul"); } public void Div(params decimal[] items) { var key = $"div{Guid.NewGuid().ToString()}"; _parameters.Add(key, items.ToArray()); } public void RestDiv() { Remove("div"); } #region private private void Remove(string charater) { var key = _parameters.Where(x => x.Key.Contains($"{charater}_")).Select(x => x.Key).OrderByDescending(x=>x).FirstOrDefault(); _parameters.Remove(key); } private decimal GetResult(string charater) { decimal result = 0; var parameters = _parameters.Where(x => x.Key.Contains($"{charater}_")).ToDictionary(x=>x.Key,y=>y.Value); var keys = parameters.Keys; //计算 foreach (var item in parameters) { result += _dic[charater].Invoke(item.Value); } foreach (var item in keys) { _parameters.Remove(item); } return result; } #endregion }
Store store = new Store(); store.Add(1, 2, 3, 4, 5); var result = store.GetAddResult(); store.Mul(8, 8); store.Mul(9, 9); store.RestMul(); result = store.GetMulResult();
