C# 委托高级使用

资料源于刘铁猛的C#视频教程

红色是主线程，其它三种是三个方法。

右边三个图分别是同步调用，异步，异步调用的示意图。

1 单播委托

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            action1.Invoke();
            action2.Invoke();
            action3.Invoke();
        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

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2 多播委托

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            //action1.Invoke();
            //action2.Invoke();
            //action3.Invoke();
            action1 += action2;
            action1 += action3;

            action1.Invoke();
        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

3 同步直接调用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            //第一种 同步直 接调用
            stu1.DoHomework();
            stu2.DoHomework();
            stu3.DoHomework();

            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(1000);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

4 同步 单播委托间接调用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            //第一种 同步 间接调用
            action1.Invoke();
            action2.Invoke();
            action3.Invoke();

            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(1000);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

5 同步 多播委托间接调用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            //第一种 同步 多播委托间接调用
            action1 += action2;
            action1 += action3;
            

            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(1000);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

6 委托 隐式异步调用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Action action1 = new Action(stu1.DoHomework);
            Action action2 = new Action(stu2.DoHomework);
            Action action3 = new Action(stu3.DoHomework);

            //异步 委托间接调用
            action1.BeginInvoke(null, null);
            action2.BeginInvoke(null, null);
            action3.BeginInvoke(null, null);


            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(1000);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

7 显式异步调用 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Thread thread1 = new Thread(new ThreadStart(stu1.DoHomework));
            Thread thread2 = new Thread(new ThreadStart(stu2.DoHomework));
            Thread thread3 = new Thread(new ThreadStart(stu3.DoHomework));

            thread1.Start();
            thread2.Start();
            thread3.Start();


            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(500);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

8 task异步线程

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace Del
{
    public delegate double Calc(double x, double y);//委托是类申明时与类平级

    class Program
    {
        static void Main(string[] args)
        {
            Student stu1 = new Student(){ ID = 1, PenColor = ConsoleColor.Yellow};
            Student stu2 = new Student(){ ID = 2, PenColor = ConsoleColor.Green};
            Student stu3 = new Student() { ID = 3, PenColor = ConsoleColor.Red };

            Task task1 = new Task(new Action(stu1.DoHomework));
            Task task2 = new Task(new Action(stu2.DoHomework));
            Task task3 = new Task(new Action(stu3.DoHomework));

            task1.Start();
            task2.Start();
            task3.Start();

            for (int i = 0; i < 10; i++)
            {
                Console.ForegroundColor = ConsoleColor.White;
                Console.WriteLine("Thread {0}", i);
                Thread.Sleep(500);
            }

        }
    }

    class Student
    {
        public int ID { get; set; }
        public ConsoleColor PenColor { get; set; }
        public  void DoHomework()
        {
            for (int i = 0; i < 5; i++)
            {
                Console.ForegroundColor = this.PenColor;
                Console.WriteLine("Student {0} doing homework {1} hours.", this.ID, i);
                Thread.Sleep(1000);
            }
        }
    }
}

6，7，8 都发生了资源的争夺，谁也不等谁。