C# 多线程传参的三种方式

方式一：使用ParameterizedThreadStart委托

使用ParameterizedThreadStart委托，线程的入口必须有一个object类型的参数，且返回类型为void。且看下面的例子：

using System;
using System.Threading;

namespace ThreadWithParameters
{
    class Program
    {
        static void Main(string[] args)
        {
            string hello = "hello world";

            //这里也可简写成Thread thread = new Thread(ThreadMainWithParameters);
            //但是为了让大家知道这里用的是ParameterizedThreadStart委托，就没有简写了
            Thread thread = new Thread(new ParameterizedThreadStart(ThreadMainWithParameters));
            thread.Start(hello);

            Console.Read();
        }

        static void ThreadMainWithParameters(object obj)
        {
            string str = obj as string;
            if(!string.IsNullOrEmpty(str))
                Console.WriteLine("Running in a thread,received: {0}", str);
        }
    }
}

ThreadMainWithParameters方法里的参数必须是object类型，ParameterizedThreadStart委托的声明：

public delegate void ParameterizedThreadStart(object obj);   //ParameterizedThreadStart委托的声明

方式二：创建自定义类

    定义一个类，在其中定义需要的字段，将线程的主方法定义为类的一个实例方法。

using System;
using System.Threading;

namespace ThreadWithParameters
{
    public class MyThread
    {
        private string data;

        public MyThread(string data)
        {
            this.data = data;
        }

        public void ThreadMain()
        {
            Console.WriteLine("Running in a thread,data: {0}", data);
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            MyThread myThread = new MyThread("hello world");

            Thread thread = new Thread(myThread.ThreadMain);
            thread.Start();

            Console.Read();
        }
    }
}

方式三：使用匿名方法

using System;
using System.Threading;

namespace ThreadWithParameters
{
    class Program
    {
        static void Main(string[] args)
        {
            string hello = "hello world";

            //如果写成Thread thread = new Thread(ThreadMainWithParameters(hello));这种形式，编译时就会报错
            Thread thread = new Thread(() => ThreadMainWithParameters(hello));
            thread.Start();

            Console.Read();
        }

        static void ThreadMainWithParameters(string str)
        {
             Console.WriteLine("Running in a thread,received: {0}", str);
        }
    }
}