添加Lesson6

2025-10-13 17:44:02 +08:00
parent 24da5481a1
commit ecf5241ed6
5 changed files with 399 additions and 0 deletions
@@ -25,6 +25,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson5_泛型", "Lesson5_
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson5_泛型练习", "Lesson5_泛型练习\Lesson5_泛型练习.csproj", "{524E1BC4-FE9A-4186-B7EE-A04323E98696}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson6_泛型约束", "Lesson6_泛型约束\Lesson6_泛型约束.csproj", "{79ACEF40-536F-48BC-B53F-92FEBD479704}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson6_泛型约束练习", "Lesson6_泛型约束练习\Lesson6_泛型约束练习.csproj", "{3BE8ABBA-44EA-4112-B88B-220C71FBFFC8}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -75,6 +79,14 @@ Global
 		{524E1BC4-FE9A-4186-B7EE-A04323E98696}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{524E1BC4-FE9A-4186-B7EE-A04323E98696}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{524E1BC4-FE9A-4186-B7EE-A04323E98696}.Release|Any CPU.Build.0 = Release|Any CPU
+		{79ACEF40-536F-48BC-B53F-92FEBD479704}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{79ACEF40-536F-48BC-B53F-92FEBD479704}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{79ACEF40-536F-48BC-B53F-92FEBD479704}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{79ACEF40-536F-48BC-B53F-92FEBD479704}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3BE8ABBA-44EA-4112-B88B-220C71FBFFC8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3BE8ABBA-44EA-4112-B88B-220C71FBFFC8}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3BE8ABBA-44EA-4112-B88B-220C71FBFFC8}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3BE8ABBA-44EA-4112-B88B-220C71FBFFC8}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>
@@ -0,0 +1,185 @@
+namespace Lesson6_泛型约束
+{
+    #region 知识回顾
+    //泛型类
+    class TestClass<T, U>
+    {
+        public T t;
+        public U u;
+
+        public U TestFun(T t)
+        {
+            return default(U);
+        }
+
+        //泛型函数
+        public V TestFun<K, V>(K k)
+        {
+            return default(V);
+        }
+    }
+    #endregion
+
+    #region 知识点一 什么是泛型约束
+    //让泛型的类型有一定限制
+    //关键字：where
+    //泛型约束一共有6种
+    //1.值类型                             where 泛型字母：struct
+    //2.引用类型                           where 泛型字母：class
+    //3.存在无参公共构造函数                where 泛型字母：new()
+    //4.某个类本身或其派生类                where 泛型字母：类名
+    //5.某个接口的派生类                    where 泛型字母：接口名
+    //6.另一个泛型类本身或派生类            where 泛型字母：另一个泛型字母
+    #endregion
+
+    #region 知识点二 各泛型约束讲解
+    class Test1<T> where T : struct
+    {
+        public T v;
+
+        public void TestFun<K>(K v) where K : struct
+        {
+
+        }
+    }
+
+    class Test2<T> where T : class
+    {
+        public T value;
+        public void TestFun<K>(K v) where K : class
+        {
+
+        }
+    }
+
+
+    class Test3<T> where T: new()
+    {
+        public T value;
+        public void TestFun<K>(K v) where K : new()
+        {
+
+        }
+    }
+    class Test1
+    {
+        
+    }
+    class Test2
+    {
+        public Test2(int i)
+        {
+
+        }
+    }
+
+
+    class Test4<T> where T : Test1
+    {
+        public T value;
+        public void TestFun<K>(K v) where K : Test1
+        {
+
+        }
+    }
+    class Test3 : Test1
+    {
+
+    }
+
+
+    interface IFly
+    {
+
+    }
+
+    class Test4 : IFly
+    {
+
+    }
+    class Test5<T> where T : IFly
+    {
+        public T value;
+        public void TestFun<K>(K v) where K : IFly
+        {
+
+        }
+    }
+
+
+    class Test6<T,U> where T : U
+    {
+        public T value;
+        public void TestFun<K,V>(K k) where K : V
+        {
+
+        }
+    }
+    #endregion
+
+    #region 知识点三 约束的组合使用
+    class Test7<T> where T : class, new()
+    {
+
+    }
+    #endregion
+
+    #region 知识点四 多个泛型有约束
+    class Test8<T,K> where T:class,new() where K : struct
+    {
+
+    }
+    #endregion
+
+    #region 总结
+    //泛型约束: 让类型有一定限制
+    //class
+    //struct
+    //new()
+    //类名
+    //接口名
+    //另一个泛型字母
+
+    //注意:
+    //1.可以组合使用
+    //2.多个泛型约束 用where连接即可
+    #endregion
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            TestClass<string,int> t = new TestClass<string,int>();
+            t.t = "123fgd";
+            t.u = 10;
+
+            t.TestFun("123");
+            t.TestFun<float,double>(123);
+
+
+            //Test1<Object> t1 = new Test1<object>;//Object类型不能为空，所以报错
+            Test1<int> t1 = new Test1<int>();//int是值类型，所以可以放
+            //t1.TestFun<Random>();//不可为空同样报错
+            t1.TestFun<float>(1.3f);
+
+
+            //Test2<int> t2 = new Test2<int>;//因为是引用类型所以值类型int会报错
+            Test2<Random> t2 = new Test2<Random>();
+            t2.TestFun<string>("123");
+            t2.TestFun<Object>(new object());
+            t2.value = new Random();
+
+
+            Test3<Test1> t3 = new Test3<Test1>();//如果Test1的构造函数是私有也会报错
+            //Test3<Test2> t4 = new Test3<Test2>();//test2有参所以报错，如果test2是无参但抽象类也会报错，必须是有公共无参构造函数的非抽象类
+            //Test3<int> t4 = new Test3<int>();//没问题，struct值类型是默认有无参构造且不会被顶替的
+
+            Test4<Test3> t4 = new Test4<Test3>();//Test3是继承约束的Test1的类，所以也不会报错
+
+            Test5<IFly> t5 = new Test5<IFly>();
+            t5.value = new Test4();//继承IFly的Test4
+
+            Test6<Test4,IFly> t6 = new Test6<Test4, IFly> ();
+            Test6<Test4, Test4> tx = new Test6<Test4, Test4>();
+        }
+    }
+}
@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>
@@ -0,0 +1,182 @@
+using System;
+
+namespace Lesson6_泛型约束练习
+{
+    #region 单例模式基类
+    class Test
+    {
+        private static Test instance = new Test();
+        public int value = 10;
+        public static Test Instance
+        {
+            get
+            {
+                return instance;
+            }
+        }
+        private Test() { }
+    }
+
+    class SingleBase<T> where T : new()
+    {
+        private static T instance = new T();
+        public static T Instance
+        {
+            get
+            {
+                return instance;
+            }
+        }
+    }
+
+    class GameManager : SingleBase<GameManager>
+    {
+        public GameManager()
+        {
+
+        }
+    }
+    #endregion
+
+    #region 利用泛型知识点，仿造ArrayList实现一个不确定数组类型的类 并 实现增删查改的方法
+    class ArrayList<T>
+    {
+        private T[] array;
+
+        private int count;
+        public ArrayList()
+        {
+            count = 0;
+            array = new T[16];
+        }
+        public void Add(T value)
+        {
+            if (count >= array.Length)
+            {
+                T[] temp = new T[Capacity * 2];
+                for (int i = 0; i < Capacity; i++)
+                {
+                    temp[i] = array[i];
+                }
+                array = temp;
+            }
+            array[count] = value;
+            count++;
+        }
+
+        public void Remove(T value)
+        {
+            int index = -1;
+            for (int i = 0; i < count; i++)//小于实际数量不小于容量
+            {
+                if (array[i].Equals(value))//不能写成array[i] == value因为不是所有类型都重载
+                {
+                    index = i;
+                    break;
+                }
+            }
+            if (index != -1)
+            {
+                for (;index < Count - 1;index++)
+                {
+                    array[index] = array[index + 1];
+                }
+                array[Count - 1] = default(T);
+                count--;
+            }
+        }
+
+        public void RemoveAt(int index)
+        {
+            if (index < 0 || index >= count)
+            {
+                Console.WriteLine("索引不合法");
+                return;
+            }
+            for (; index < Count - 1; index++)
+            {
+                array[index] = array[index + 1];
+            }
+            array[Count - 1] = default(T);
+            count--;
+        }
+
+        public T this[int index]
+        {
+            get
+            {
+                if (index < 0 || index >= count)
+                {
+                    Console.WriteLine("索引不合法");
+                    return default(T);
+                }
+                return array[index];
+            }
+            set
+            {
+                if (index < 0 || index >= count)
+                {
+                    Console.WriteLine("索引不合法");
+                    return;
+                }
+                array[index] = value;
+            }
+        }
+        /// <summary>
+        /// 得容量和实际数量
+        /// </summary>
+        public int Capacity
+        {
+            get
+            {
+                return array.Length;
+            }
+        }
+        public int Count
+        {
+            get
+            {
+                return count;
+            }
+        }
+    }
+    #endregion
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            ArrayList<int> array = new ArrayList<int>();
+            Console.WriteLine(array.Count);
+            Console.WriteLine(array.Capacity);
+            array.Add(1);
+            array.Add(2);
+            array.Add(3);
+            Console.WriteLine(array.Count);
+            Console.WriteLine(array.Capacity);
+            Console.WriteLine(array[1]);
+            Console.WriteLine(array[-1]);
+            Console.WriteLine(array[5]);
+            array.Remove(2);
+            Console.WriteLine(array.Count);
+            Console.WriteLine("/////////////////");
+            for (int i = 0; i < array.Count; i++)
+            {
+                Console.Write(array[i]);
+            }
+            Console.WriteLine();
+            Console.WriteLine("/////////////////");
+            array.RemoveAt(0);
+            for (int i = 0; i < array.Count; i++)
+            {
+                Console.Write(array[i]);
+            }
+            Console.WriteLine();
+            Console.WriteLine("/////////////////");
+            array[1] = 555;
+            for (int i = 0; i < array.Count; i++)
+            {
+                Console.Write(array[i]);
+            }
+        }
+    }
+}