界面和线程交互之简单使用说明

在进行多线程设计过程中，最重要的就是实现线程同步和线程界面交互。如果想实现线程同步，可以通过lock锁来进行；而如果要想线程和界面交互，则需要利用委托来进行，下面请看代码：

using System;
using System.Windows.Forms;
using System.Threading;

namespace UpdateUIFromThreadAPP
{
    public partial class MainFrm : Form
    {
        public MainFrm()
        {
            InitializeComponent();
            this.DoubleBuffered = true;
        }

        private object lockShopkeeper = new object();  //the flag of locking state
        private Good[] goods;  // good array
        private static int sum = 0;  // summery of the goods' price

      

        private void MainFrm_Load(object sender, EventArgs e)
        {
            InitGoods();
            OpenThread();
        }

        //init the storage
        private void InitGoods()
        {
            Good cabbage = new Good { GoodName = "白菜", GoodNumber = 20, GoodPrice = 12 };
            Good radish = new Good { GoodName = "萝卜", GoodNumber = 43, GoodPrice = 3 };
            Good celery = new Good { GoodName = "芹菜", GoodNumber = 15, GoodPrice = 7 };
            Good onion = new Good { GoodName = "洋葱", GoodNumber = 78, GoodPrice = 2 };
            Good egg = new Good { GoodName = "鸡蛋", GoodNumber = 124, GoodPrice = 1 };

            goods = new Good[5];  
            goods[0] = cabbage;
            goods[1] = radish;
            goods[2] = celery;
            goods[3] = onion;
            goods[4] = egg;

            for (int i = 0; i < 5; i++)
            {
                Good temp = goods[i];
                ListViewItem lvi = new ListViewItem();
                lvi.Text = temp.GoodName + " 数量：" + temp.GoodNumber + " 单价：" + temp.GoodPrice + " 总价：" + temp.GoodNumber * temp.GoodPrice;
                lsvStoreGoods.Items.Add(lvi);  //add the info to the first listview
            }
        }

        //generate the random num of buying
        private int SellNum()
        {
            Random ran = new Random();
            return ran.Next(1,10);
        }

        //get the index of a good
        private int GetGoodIndex()
        {
            Random ran = new Random();
            return ran.Next(0, 5);
        }

        /// <summary>
        /// start to buy goods in 1000 threads
        /// </summary>
        private void OpenThread()
        {
            int threadNum = 1000;   // the person buying the goods, here I sets it to 1000.
            Thread[] thread = new Thread[threadNum];
            for (int i = 0; i < threadNum; i++)
            {
                Thread _thread = thread[i];
                _thread = new Thread(new ParameterizedThreadStart(Open));
                _thread.Start((object)goods[GetGoodIndex()]);
            }
        }

        private void Open(object _good)
        {
            Good good = _good as Good;
            lock (lockShopkeeper)
            {
                int _selNum = SellNum();
                if (good.GoodNumber >= _selNum)
                {
                    good.GoodNumber = good.GoodNumber - _selNum;
                    Thread.Sleep(500);
                    UpdateStorage(good);
                    UpdateSell(good, _selNum);
                    UpdateProfit(good, _selNum);
                }
                else
                {
                    if (good.GoodNumber > 0)
                    {
                        Thread.Sleep(500);
                        _selNum = good.GoodNumber;
                        good.GoodNumber = 0;
                        UpdateStorage(good);
                        UpdateSell(good, _selNum);
                        UpdateProfit(good, _selNum);
                    }
                }
            }
        }

        private delegate void UpdateStorageDelegate(Good good);
        private delegate void UpdateSellDelegate(Good good, int num);
        private delegate void UpdateProfitDelegate(Good good, int num);
        private delegate void UpdateProgressInfoDelegate(int sum);
        private delegate void UpdateProgressDelegate(int sum);

        private void UpdateStorage(Good good)
        {
            if (lsvStoreGoods.InvokeRequired)
            {
                lsvStoreGoods.Invoke(new UpdateStorageDelegate(UpdateStorage), good);
            }
            else
            {
                ListViewItem lvi = lsvStoreGoods.FindItemWithText(good.GoodName, false, 0, true);
                lvi.Text = good.GoodName + " 数量：" + good.GoodNumber + " 单价：" + good.GoodPrice + " 总价：" + good.GoodNumber * good.GoodPrice;
            }
        }

        private void UpdateSell(Good good, int num)
        {
            if (lsvSellGoods.InvokeRequired)
            {
                lsvSellGoods.Invoke(new UpdateSellDelegate(UpdateSell),good,num);
            }
            else
            {
                ListViewItem lvi=new ListViewItem();
                lvi.Text="卖出"+good.GoodName+" 单价："+good.GoodPrice+" 数量："+num+" 获得利润："+num*good.GoodPrice;
                lsvSellGoods.Items.Add(lvi);
            }
        }

        private void UpdateProfit(Good good, int num)
        {
            if (lsvTotal.InvokeRequired)
            {
                lsvTotal.Invoke(new UpdateProfitDelegate(UpdateProfit), good, num);
            }
            else
            {
                ListViewItem lvi = lsvTotal.FindItemWithText("销售总额", false, 0, true);
                sum += num * good.GoodPrice;
                UpdateProgress(sum);
                UpdateProgressInfo(sum);
                lvi.Text = "销售总额" + sum;
            }
        }

        private void UpdateProgress(int sum)
        {
            if (pbInfo.InvokeRequired)
            {
                pbInfo.Invoke(new UpdateProgressDelegate(UpdateProgress), sum);
            }
            else
            {
                pbInfo.Value = sum;
            }
        }

        private void UpdateProgressInfo(int sum)
        {
            if (lblInfo.InvokeRequired)
            {
                lblInfo.Invoke(new UpdateProgressInfoDelegate(UpdateProgressInfo), sum);
            }
            else
            {
                lblInfo.Text = (double)((double)sum / (double)754) * 100 + "%";
            }
        }

    }
}

看下跑的效果图：