Synchronization of old projects

Part1

C#核心/Lesson9_封装-拓展方法练习/Program.cs

@@ -0,0 +1,67 @@
+namespace Lesson9_封装_拓展方法练习
+{
+    static class Tools
+    {
+        public static int IntSqrt(this int i)
+        {
+            return i*i;
+        }
+        public static void Suicide(this player p)
+        {
+            Console.WriteLine("{0}自杀了",p.name);
+        }
+    }
+    class player
+    {
+        public string name;
+        public int hp, atk, def;
+        public player()
+        {
+            name = "null";
+            hp = 0;
+            atk = 0;
+            def = 0;
+        }
+        public player(string name,int hp,int atk,int def)
+        {
+            this.name =name;
+            this.hp = hp;
+            this.atk = atk;
+            this.def = def;
+        }
+        public void Attack() 
+        {
+            Console.WriteLine("{0}攻击了，攻击值{1}",name,atk);
+        }
+        public void Defense() 
+        { 
+            Console.WriteLine("{0}防御了，防御值{1}",name,def); 
+        }
+        public void Move() 
+        {
+            Console.WriteLine("{0}移动了",name);
+        }
+        public void GetHurt() 
+        {
+            Console.WriteLine("{0}受伤了,剩余{1}hp",name,hp);
+        }
+    }
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            player p = new player();
+            p.Attack();
+            p.Defense();
+            p.Move();
+            p.GetHurt();
+            p.Suicide();
+            player p2 = new player("HK",100,100,100);
+            p2.Attack();
+            p2.Defense();
+            p2.Move();
+            p2.GetHurt();
+            p2.Suicide();
+        }
+    }
+}