Winform UI线程和处理线程交互（进度更新显示）

在界面开发过程中，会遇到耗时较长的处理过程，一般会将耗时较长的处理放到单独的线程中。然后在界面显示处理进度信息。

实现改效果的两种方式记录：

1. 使用委托：

       //定义委托，在线程中使用
        private delegate void SetProgressDelegate(int value, string text);
        private delegate void FinishDelegate();

        public Form1()
        {
            InitializeComponent();
        }

        private void btnStart_Click(object sender, EventArgs e)
        {
            //开启线程
            new Thread(new ThreadStart(SubThread)).Start();
        }

        //线程函数
        private void SubThread()
        {
            FinishDelegate finish = new FinishDelegate(Finish);
            SetProgressDelegate setProgress = new SetProgressDelegate(SetProgress);
            for (int i = 0; i <= 100; i++)
            {
                //跨线程调用委托
                this.Invoke(setProgress, new object[] { i, string.Format("{0}%", i) });
                Thread.Sleep(100);  //模拟耗时任务
            }
            this.Invoke(finish);
        }
        private void SetProgress(int value, string text)
        {
            this.progressBar.Value = value;
            this.lblProgressText.Text = text;
        }

        private void Finish()
        {
            MessageBox.Show("处理完成！");
        }

2. 使用异步线程上下文 SynchronizationContext

       //UI线程的上下文
        private SynchronizationContext mUIThreadSyncContext;

        public Form1()
        {
            InitializeComponent();
            //初始化
            mUIThreadSyncContext = SynchronizationContext.Current;
        }

        private void btnStart_Click(object sender, EventArgs e)
        {
            //开启线程
            new Thread(new ThreadStart(SubThread)).Start();
        }

        //线程函数
        private void SubThread()
        {
            for (int i = 0; i <= 100; i++)
            {
                //更新UI线程
                mUIThreadSyncContext.Post(new SendOrPostCallback(SetProgress), i);
                Thread.Sleep(100);  //模拟耗时任务
            }
            mUIThreadSyncContext.Post(new SendOrPostCallback(Finish), null);
        }

        private void SetProgress(object state)
        {
            this.progressBar.Value = Convert.ToInt32(state);
            this.lblProgressText.Text = state.ToString() + "%";
        }

        private void Finish(object state)
        {
            MessageBox.Show("处理完成！");
        }

原文地址：https://blog.csdn.net/tongxin1004/article/details/80979043