多线程

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Threading; //线程操作的类在这个命名空间下.

namespace C02多线程
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            //关闭控件的跨线程访问检查 
            TextBox.CheckForIllegalCrossThreadCalls = false;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int sum = 0;
            for (int i = 0; i < 999999999; i++)
            {
                sum += i;
            }

            MessageBox.Show("ok");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //创建1个线程对象 并为这个线程对象指定要执行的方法.
            Thread thread = new Thread(TestThread);
            //设置线程为后台线程.
            thread.IsBackground = true;
            //开启线程
            thread.Start();

            //线程默认情况下都是前台线程.
            //要所有的前台线程退出以后 程序才会退出.
            //后台线程 只要所有的前台线程结束 后台线程就会立即结束.
            //进程里默认的线程我们叫做主线程或者叫做UI线程. 
            //线程什么时候结束 该线程执行的方法执行完以后  线程就自动退出.


            //多个线程访问同一资源  可能造成不同步的情况. 这个叫做 线程重入.
            //th.Abort(); 强行停止线程.
            //Thread.Sleep(1000);//将当前线程暂停 单位毫秒
            //Thread.CurrentThread;得到当前线程的引用


            //线程调用带参数的方法 
            //创建1个ParameterizedThreadStart委托对象.为这个委托对象绑定方法.
            //将委托对象通过构造函数传入线程对象
            //启动线程的时候调用Start()的重载 将参数传入.
        }


        //准备让线程去调用.
        private void TestThread()
        {
            int sum = 0;
            for (int i = 0; i < 999999999; i++)
            {
                sum += i;
            }
            MessageBox.Show("ok");
        }

        private void CountNunm()
        {
            //使用lock加锁  请联想你上厕所的情况
            lock (this)
            {
                for (int i = 0; i < 10000; i++)
                {
                    int num = int.Parse(textBox1.Text.Trim());
                    num++;
                    //Thread.Sleep(500);//将当前线程暂停
                   // Thread.CurrentThread.Abort();
                    //Thread th = Thread.CurrentThread;
                    //th.Abort();
                    //if (num == 5000)
                    //{
                    //    th.Abort();
                    //}
                    textBox1.Text = num.ToString();
                }
            }
        }
        Thread th;
        private void button3_Click(object sender, EventArgs e)
        {
            th = new Thread(CountNunm);
            th.Name = "哈哈线程";
            th.IsBackground = true;

            th.Start();



            //Thread th1 = new Thread(CountNunm);
            //th1.IsBackground = true;
            //th1.Start();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            //ThreadStart s = new ThreadStart(CountNunm); 
            //Thread th = new Thread(CountNunm); 
            ParameterizedThreadStart s = new ParameterizedThreadStart(TestThreadParsms);
            Thread t = new Thread(s);
            t.IsBackground = true;
            t.Start("你好啊");   
        }



        private void TestThreadParsms(object obj)
        {
            Console.WriteLine(obj.ToString());
        }

    }
}