2017-5-4 线程

线程：
帮助老板干活的，不会干扰老板的正常工作

如果一段代码的执行需要时间，那么必须开启一个新线程来执行，
如果不开线程，窗口会出现假死

开线程：

Thread th = new Thread(委托);
th.IsBackground = true; //设置后台线程
th.Start();

线程默认是不允许跨线程访问对象的
在构造函数中用Control.CheckForIllegalCrossThreadCalls = false; 可以允许跨线程访问对象。
 关闭线程：

th.Abort();

线程最多可以执行一个参数的方法，这个参数必须是object类型

利用线程做一个三级连动的小程序：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace 线程联系__小程序___2017_5_4
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            Control.CheckForIllegalCrossThreadCalls = false;
        }
        Thread th = null;
        Thread th1 = null;
        Thread th2 = null;
        private void button1_Click(object sender, EventArgs e)
        {
           th = new Thread(test1);
            th.IsBackground = true;
            th.Start();
            th1 = new Thread(test2);
            th1.IsBackground = true;
            th1.Start();
            th2 = new Thread(test3);
            th2.IsBackground = true;
            th2.Start();
         }
      

        private void button2_Click(object sender, EventArgs e)
        {
            th.Abort();
            th1.Abort();
            th2.Abort();
        }
        public void test1()
        {
            Random r = new Random();

            string[] name = new string[] { "郑倩", "徐强", "子君", "子轩", "郑剑" };
            while (true)
            {
                int a = r.Next(1, name.Length);
                textBox1.Text = name[a];

                Thread.Sleep(100);
            }
        }
        public void test2()
        {
            Random r = new Random();


            string[] city = new string[] { "博兴", "张店", "马桥", "济南", "青岛" };


            while (true)
            {
                int b = r.Next(1, city.Length);


                textBox2.Text = city[b];



                Thread.Sleep(100);
            }
        } 
 
        public void test3()
        {
            Random r = new Random();
            string[] events = new string[] { "吃汉堡", "旅游", "淘气", "上学", "写代码", "玩" };
            while (true)
            {
                int c = r.Next(1, events.Length);
                textBox3.Text = events[c];
                Thread.Sleep(100);
            }      
          
        
               
        }

      }
}