383 Task.ContinueWith

示例

Program.cs

using System.Diagnostics;
namespace TaskExample
{
    internal class Program
    {
        static void Main(string[] args)
        {
            UpCounter upCounter = new UpCounter();
            DownCounter downCounter = new DownCounter();
            int maxNo = 100;
            Task<long> t1 = Task<long>.Factory.StartNew(() =>
            {
                return upCounter.CountUp(maxNo);
            });
            Task continuationt1 = t1.ContinueWith((antecedent) =>
            {
                Console.WriteLine($"\nt1: {t1.Result}");
            });
            Task<SumData> t2 = Task.Factory.StartNew(() =>
            {
                return downCounter.CountDown(maxNo);
            });
            Task continuationt2 = t2.ContinueWith((antecedent) =>
            {
                Console.WriteLine($"\nt2: {t2.Result.Sum}");
            });
            //Task.WaitAll(continuationt1, continuationt2);
            //SumData sumData = t2.Result;
            //Console.WriteLine($"t2: {sumData.Sum}");
            Console.WriteLine("t1 and t2 completed.");
            Console.ReadKey();
        }
    }
    class UpCounter
    {
        public long CountUp(int count)
        {
            long sum = 0;
            Console.WriteLine("\nCount-Up starts.");
            for (int i = 1; i <= count; i++)
            {
                Console.Write($"Up: {i}, ");
                sum += i;
                //Task.Delay(300).Wait(); //Create a new task, and the new task pause the current task by wait method
            }
            Console.WriteLine("\nCount-Up ends.");
            return sum;
        }
    }
    class DownCounter
    {
        public SumData CountDown(int count)
        {
            long sum = 0;
            Console.WriteLine("\nCount-Down starts.");
            for (int i = count; i >= 1; i--)
            {
                Console.Write($"Down: {i}, ");
                sum += i;
                //Task.Delay(300).Wait(); //Create a new task, and the new task pause the current task by wait method
            }
            Console.WriteLine("\nCount-Down ends.");
            return new SumData() { Sum = sum };
        }
    }
    class SumData
    {
        public long Sum { get; set; }
    }
}