C#中，Task(Action<object> action, object state)遇见的问题

Question

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

using System.Threading;

namespace ConsoleApp中task的状态
{
    class Program
    {
        private static void Method(int i)
        {
            i =i *1000;
            Thread.Sleep(i);
        }
        static void Main(string[] args)
        {
            Action<int> action = new Action<int>(Method);

            Task task1 = new Task(action,null);
            task1.Start();


        }
    }
}

 代码这一部分，Task task1 = new Task(action,null);

提示报错原因是： 参数 1: 无法从“System.Action<int>”转换为“System.Action”   

 

Answer 1

task的重载没有int这种泛型，只有Action<object>，你传递Action<int>当然没法转换成action，改成下面就行了

        private static void Method(object state)
        {
            var o = (Data)state;
            int a = o.x;
            int b = o.y;
            int i = a * b;
            Console.WriteLine($"{a}和{b}相乘的结果是{i}");
        }
        static void Main(string[] args)
        {
            Action<object> action = new Action<object>(Method);
            Task task1 = new Task(action, new Data { x=1,y=2});
            task1.Start();

            Console.ReadKey();
        }
        public class Data { public int x { get; set; }public int y { get; set; } }