Charater 6

6.16 this关键字

class Program
    {
        static void Main(string[] args)
        {
            var compare = new Compare();
            Console.WriteLine(compare.compareValue(10));
        }
    }
    class Compare
    {
        int myValue = 10;
        public int compareValue(int myValue)
        {
            return myValue > this.myValue ? myValue : this.myValue;
            //     参数        字段          参数        字段
        }
    }

6.17 索引器 indexer[]

 class Program
    {
        static void Main(string[] args)
        {
            var employee = new Employee();
            employee[0] = "Hongyong";
            employee[1] = "Zhao";
            employee[2] = "Suzhou";
            Console.WriteLine("{0} {1} lives in {2}.",employee[0],employee[1],employee[2]);
        }
    }
    class Employee
    {
        public string lastName;
        public string firstName;
        public string cityOfBirth;
        public string this[int index] //indexer格式：修饰符+返回类型+this[int index]
        {
            get 
            {
                switch (index)
                {
                    case 0:return lastName;
                    case 1:return firstName;
                    case 2:return cityOfBirth;
                    default:
                        throw new ArgumentOutOfRangeException("index");
                }
            }
            set 
            {
                switch (index)
                {
                    case 0: lastName = value;
                        break;
                    case 1:firstName = value;
                        break;
                    case 2:cityOfBirth = value;
                        break;
                    default:
                        throw new ArgumentOutOfRangeException("index");
                }
            }
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            var empy1 = new Employee();
            Console.WriteLine("{0}  {1}",empy1[0],empy1[1]);//默认值为0
            empy1[0] = 123;
            empy1[1] = 234;
            Console.WriteLine("{0}  {1}", empy1[0], empy1[1]);
        }
    }
    class Employee
    {
        int temp0;
        int temp1;
        public int this[int index]
        {
            get { return (0 == index) ? temp0 : temp1; }
            set 
            {
                if (0 == index)
                {
                    temp0 = value;
                }
                else
                    temp1 = value;
            }
        }
    }

6.18 访问器的访问修饰符 public protected private

class Program
    {
        static void Main(string[] args)
        {
            var albert = new Albert();
            string a = albert.Person("zhaohongyong");
            Console.WriteLine(a);
        }
    }
    class Albert
    {
        public string Name { get; private set; } //只允许在类中进行设置属性
        public string Person(string name)
        {
            Name = name;
            return Name;
        }
    }

6.20 分部方法 partial

class Program
    {
        static void Main(string[] args)
        {
            var alert = new Alert();
            alert.Add(3, 5);
        }
    }
    partial class Alert
    {
        partial void PrintSum(int x, int y);//定义分部方法
        public void Add(int x,int y)
        {
            PrintSum(x, y);
        }
    }
    partial class Alert
    {
        partial void PrintSum(int x, int y)  //实现部分
        {
            Console.WriteLine("Sum is {0}",x+y);
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            var alert = new Alert();
            alert.Calc(3, 5);
        }
    }
    partial class Alert
    {
        partial void PrintCalc(int x, int y);
        public void Calc(int x ,int y)
        {
            PrintCalc(x, y);
        }
    }
    partial class Alert
    {
        partial void PrintCalc(int x, int y)
        {
            Console.WriteLine(x + y);
        }
    }

Charater 7

7.1 类继承 冒号

class Program
    {
        static void Main(string[] args)
        {
            var calc = new CalcInter();
            calc.x = 8;
            calc.y = 2;
            Console.WriteLine(calc.CalcDiv(calc.x, calc.y)); 
        }
    }
    class Calc
    {
        public int x, y;
        public double CalcAdd(int x,int y)
        {
            return x + y;
        }
    }
    class CalcInter:Calc
    {
        public int field1, field2;
        public double CalcDiv(int x,int y)
        {
            return x / y;
        }
    }

7.4 屏蔽基类的成员 new

class Program
    {
        static void Main(string[] args)
        {
            var someClass = new SomeClass();
            someClass.Method1("someclass test");
            Console.WriteLine(someClass.field1 );
            var otherClass = new OtherClass();
            otherClass.Method1("otherclass test");
            Console.WriteLine(otherClass.field1);
        }
    }
    class SomeClass
    {
        public string field1 = "SomeClass field1";
        public void Method1(string value)
        {
            Console.WriteLine("SomeClass.Method1 :{0}",value);
        }
    }
    class OtherClass : SomeClass
    {
        new public string field1 = "SomeClass field2";//屏蔽数据成员 new 相同类型+相同名称
        new public void Method1(string value)  //屏蔽函数成员 new 相同的签名，签名=名称+参数列表，不包括返回类型
        {
            Console.WriteLine("OtherClass.Method1:{0}",value);
        }
    }

7.5 基类访问 base

 class Program
    {
        static void Main(string[] args)
        {
            var otherClass = new OtherClass();
            string other = otherClass.Field1;  //派生类中字段
            Console.WriteLine( other); //派生类中的字段
            otherClass.PrintField1();
        }
    }
    class SomeClass
    {
        public string Field1 = "Field1--In the base class";//基类数据成员
    }
    class OtherClass : SomeClass
    {
        new public string Field1 = "Field1-- In the derived class";//屏蔽基类数据成员
        public void PrintField1()
        {
            Console.WriteLine(Field1);  //继承类中Fiels1
            Console.WriteLine(base.Field1);  //基类访问符base
        }
    }

7.6 使用基类引用

class Program
    {
        static void Main(string[] args)
        {
            var derivedClass = new Myderived();
            derivedClass.Print();
            var mybc = (MyBaseClass)derivedClass;//将derivedClass变量赋值给mybc，类型转换为基类类型，可见范围缩小。
            mybc.Print();
        }
    }
    class MyBaseClass
    {
        public void Print()
        {
            Console.WriteLine("This is the base class");
        }
    }
    class Myderived:MyBaseClass
    {
        new public void Print()
        {
            Console.WriteLine("This is the derived class");
        }
    }

 class Program
    {
        static void Main(string[] args)
        {
            var derivedClass = new Myderived();
            derivedClass.Print();
            var mybc = (MyBaseClass)derivedClass;
            mybc.Print();
        }
    }
    class MyBaseClass
    {
        virtual public void Print()
        {
            Console.WriteLine("This is the base class");
        }
    }
    class Myderived:MyBaseClass
    {
        override public void Print()
        {
            Console.WriteLine("This is the derived class");
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            var derivedClass = new Myderived();
            var secondDerived = new SecondDerived();
            derivedClass.Print();
            var mybc = (MyBaseClass)secondDerived;
            mybc.Print();
        }
    }
    class MyBaseClass
    {
        virtual public void Print()
        {
            Console.WriteLine("This is the base class");
        }
    }
    class Myderived:MyBaseClass
    {
        override public void Print()
        {
            Console.WriteLine("This is the derived class");
        }
    }
    class SecondDerived:Myderived
    {
        override public void Print()
        {
            Console.WriteLine("this is the second derived class");
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            var secondDrived = new SecondDerived();
            secondDrived.Print();  //屏蔽了父类的方法
            var myBaseClass = (MyBaseClass)secondDrived;
            myBaseClass.Print();  //通过链条传递到最后拥有override的方法中
        }
    }
    class MyBaseClass
    {
        virtual public void Print()
        {
            Console.WriteLine("This is the base class");
        }
    }
    class Myderived:MyBaseClass
    {
        override public void Print()
        {
            Console.WriteLine("This is the derived class");
        }
    }
    class SecondDerived:Myderived
    {
        new public void Print()
        {
            Console.WriteLine("this is the second derived class");
        }
    }

class Program
    {
        static void Main(string[] args)
        {
            var myDerived = new Myderived();
            var myBase = (MyBaseClass)myDerived;
            Console.WriteLine(myDerived.MyInt);
            Console.WriteLine(myBase.MyInt);
        }
    }
    class MyBaseClass
    {
        private int myInt = 5;
        virtual public int MyInt
        {
            get { return myInt; }
        }
    }
    class Myderived:MyBaseClass
    {
        private int myInt = 15;
        override public int MyInt
        {
            get { return myInt; }
        }
    }
    class SecondDerived:Myderived
    {
        private int myInt = 5;
        override public int MyInt
        {
            get { return myInt; }
        }
    }

7.11抽象类：抽象类

class Program
    {
        static void Main(string[] args)
        {
            var Derived = new DerivedClass();
            Derived.MyInt = 56;
            Derived.PrintStuff("helloworld");
            Derived.TriangLeSideCount = 4;
            Derived.SideLength = 5;
            Console.WriteLine(Derived.MyInt);
        }
    }
    abstract class AbClass
    {
        public int SideLength = 10;//数据成员不可以声明为abstract
        public int TriangLeSideCount = 3;
        abstract public int MyInt { get; set; } //抽象属性
        abstract public void PrintStuff(string s); //抽象方法
    }
    class DerivedClass:AbClass
    {
        public override void PrintStuff(string s)
        {
            Console.WriteLine(s);
        }
        private int _myInt;
        public override int MyInt { get { return _myInt; } set { _myInt = value; } }
    }