command

DesignPattern/DesignPattern/Patterns/CommandPattern.cs

@@ -0,0 +1,84 @@
+namespace DesignPattern.Patterns
+{
+    interface ICommand
+    {
+        void Execute();
+    }
+
+    class User
+    {
+        private List<ICommand> _commands = new List<ICommand>();
+
+        public void AddCommand(ICommand command)
+        {
+            _commands.Add(command);
+        }
+
+        public void AddCommand(StockBroker broker, string symbol, TxType txType, int qty)
+        {
+            ICommand cmd = new StockCommand(broker, symbol, txType, qty);
+            _commands.Add(cmd);
+        }
+
+        public void ExecuteAll()
+        {
+            foreach (var cmd in _commands)
+            {
+                cmd.Execute();
+            }
+        }
+    }
+
+    class StockCommand : ICommand
+    {
+        private StockBroker _broker;
+        private string _symbol;
+        private TxType _txType;
+        private int _qty;
+
+        public StockCommand(StockBroker broker, string symbol, TxType txType, int qty)
+        {
+            _broker = broker;
+            _symbol = symbol;
+            _txType = txType;
+            _qty = qty;
+        }
+
+        public void Execute()
+        {
+            _broker.Process(_symbol, _txType, _qty);
+        }
+    }
+
+    enum TxType
+    {
+        Buy,
+        Sell
+    }
+
+    class StockBroker
+    {
+        public void Process(string stockSymbol, TxType txType, int qty)
+        {
+            Console.WriteLine($"{txType}, {stockSymbol}, {qty}");
+        }
+    }
+
+    class CommandClient
+    {
+        public static void Work()
+        {
+            var broker = new StockBroker();
+
+            User user = new User();
+
+            ICommand cmd = new StockCommand(broker, "MSFT", TxType.Buy, 150);
+            user.AddCommand(cmd);
+            user.AddCommand(broker, "AMZN", TxType.Sell, 2000);
+            user.AddCommand(broker, "BRK.B", TxType.Buy, 5000);
+            user.AddCommand(broker, "APPL", TxType.Sell, 1000);
+
+            user.ExecuteAll();
+        }
+    }
+}

DesignPattern/DesignPattern/Program.cs

@@ -6,6 +6,8 @@ class Program
 {
     static void Main(string[] args)
     {
-        FactoryClient.Work();
+        // FactoryClient.Work();
+
+        CommandClient.Work();
     }
 }