• c#中BackGroundWorker控件使用实例


    一、BackGroundWorker工作步骤

    1.向窗体中拖入一个BackGroundWorker控件。

    2.在某个方法或者事件中,调用BackGroundWorker的RunWorkerAsync()方法。

    3.该方法为异步操作,将自动引发BackGroundWorker的DoWork事件。

    4.调用ReportProgress方法将引发ProgressChanged事件。

    二、一个使用了BackGroundWorker的例子

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

    using System.Threading;
    using System.Data.SqlClient;


    //该用例需要一个名为bgwTestDB的Sql Server数据库
    //数据库中应包含tbBgwTest表。
    //表中有data1、data2两列。
    //数据库中还需要一个存储过程,sql语句如下:
    /***************
    create procedure insertOneData
    @data1 nchar(10),
    @data2 int
    as
    insert into tbBgwTest (data1,data2) values (@data1, @data2)
    ********************/

    namespace winBackgroundWorkerTest
    {
        public partial class backgroundWorkerTest : Form
        {
            int count = 30;

            public backgroundWorkerTest()
            {
                InitializeComponent();
            }

            private void btnAdd_Click(object sender, EventArgs e)
            {
                //1.调用bgwInsertData的RunWorkerAsync方法,用来引发DoWork事件
                bgwInsertData.RunWorkerAsync(count);
            }

            private void bgwInsertData_DoWork(object sender, DoWorkEventArgs e)
            {
                BackgroundWorker worker = sender as BackgroundWorker;
                //2.在DoWork中调用自定义函数,并将引发DoWork事件的sender传递出去
                insertData(worker);
            }

            private void bgwInsertData_ProgressChanged(object sender, ProgressChangedEventArgs e)
            {
                progressBar1.Value = e.ProgressPercentage;
            }

            //自定义函数 insertData()
            private void insertData(BackgroundWorker worker)
            {
                SqlConnection conn = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=bgwTestDB;Integrated Security=True");

                SqlCommand cmd = new SqlCommand("insertOneData", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.Add("data1", SqlDbType.NChar, 10);
                cmd.Parameters.Add("data2", SqlDbType.Int);

                for (int i = 0; i < count; i++)
                {
                    try
                    {
                        conn.Open();
                        cmd.Parameters["data1"].Value = i + 1;
                        cmd.Parameters["data2"].Value = i + 1;
                        cmd.ExecuteNonQuery();

                        //3.调用worker的ReportProgress函数,用来引发事件ProgressChanged
                        worker.ReportProgress(i, worker);
                    }
                    catch(Exception ex)
                    {
                        MessageBox.Show(ex.Message);
                    }
                    finally
                    {
                        if (conn.State == ConnectionState.Open)
                            conn.Close();
                    }

                    Thread.Sleep(50);
                }
            }

            private void bgwInsertData_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
            {
                if (e.Error != null)
                {
                    MessageBox.Show(e.Error.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    return;
                }
                else if (e.Cancelled)
                {
                    MessageBox.Show("取消操作!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    return;
                }
                else
                    MessageBox.Show("操作成功!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }
    }

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  • 原文地址:https://www.cnblogs.com/moss_tan_jun/p/2008837.html
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