using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Threading;

namespace ProgessBarTest

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            this.btn_Calculate.Enabled = false;//设置计算按键不可用

            this.tb_result.Text = string.Empty;//清空文本框内容

            this.btn_cancel.Enabled = true; //设置取消按键可用

            this.progressBar1.Value = 0;

            //启动后台线程，实例化一个CalcInput对象传给新线程

            backgroundWorker1.RunWorkerAsync(

                                            new CalcInput(

                                                            int.Parse(this.tb_x.Text),

                                                            int.Parse(this.tb_y.Text)

                                                            )

                                            );

        }

        private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)

        {

            //从DoWorkEventArgs类型参数e的Argument属性得到传入的对象实例

            CalcInput input = (CalcInput)e.Argument;

            //模拟执行时间

            for (int i = 0; i < 10; i++)

            {

                input.x += input.y;

                Thread.Sleep(300);

                if(backgroundWorker1.CancellationPending)

                {

                    e.Cancel = true;

                    return;

                }

            }

            //将计算结果交给参数e的Result属性

            e.Result = input.x;

        }

        private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)

        {

            this.btn_Calculate.Enabled = true;//设置计算按键不可用

            if (e.Cancelled)

            {

                this.tb_result.Text = "计算中断";

            }

            else

            {

                this.tb_result.Text = e.Result.ToString();

            }

            this.btn_cancel.Enabled = false;

            this.progressBar1.Value = 100;

        }

        private void btn_cancel_Click(object sender, EventArgs e)

        {

            backgroundWorker1.CancelAsync();

        }

    }

}