C # initial test of BackgroundWorker,

C # initial test of BackgroundWorker,

 

/* * Created by SharpDevelop. * User: Administrator * Date: 2017/7/31 * Time: 16:18 *  * To change this template use Tools | Options | Coding | Edit Standard Headers. */using System;using System.Collections.Generic;using System.Drawing;using System.Windows.Forms;using System.Threading;using System.ComponentModel;namespace App{    /// <summary>    /// Description of MainForm.    /// </summary>    public partial class MainForm : Form    {        private BackgroundWorker bw;        public MainForm()        {            //            // The InitializeComponent() call is required for Windows Forms designer support.            //            InitializeComponent();            //            // TODO: Add constructor code after the InitializeComponent() call.            //        }        void process1_Exited(object sender, EventArgs e)        {            // TODO: Implement process1_Exited        }        private void MainForm_Load(object sender, EventArgs e)        {        }        void button1_Click(object sender, EventArgs e)        {            bw = new BackgroundWorker();            bw.WorkerReportsProgress = true;            bw.WorkerSupportsCancellation = true;            bw.DoWork += DoWork;            bw.RunWorkerCompleted += RunWorkerComplated;            bw.ProgressChanged += UpdateButtonText;            bw.RunWorkerAsync();        }        void RunWorkerComplated(object sender, RunWorkerCompletedEventArgs e)        {            MessageBox.Show("ok");        }        void DoWork(object sender, DoWorkEventArgs e)        {            for (int i = 1; i <= 100; i++)            {                (sender as BackgroundWorker).ReportProgress(i);                label1.Text = i.ToString();                Thread.Sleep(100);            }        }        void UpdateButtonText(object sender, ProgressChangedEventArgs e)        {            button2.Text = e.ProgressPercentage.ToString();        }    }}

Detours:

1. The UI control cannot be manipulated in the DoWork method.

2. Call the ReportProgress method in the DoWork event to manipulate the UI control in the ProgressChanged event.

3. The WorkerReportsProgress attribute must be set to true. (the default value is false. Because of this, it takes a lot of time to find the cause)