如何使用后台工作者+进度条进行C＃登录 [英] How to do a C# login using background worker + progress bar

问题描述

有人可以向我澄清背景工作者的实际工作方式。我想做一个简单的登录表单，它会在用户点击登录后显示登录进度，因为通常需要很长时间才能阅读登录详细信息，因此我想更新用户而不是让ui挂起。



我已经尝试了下面的代码，但我不知道如何或在哪里保存结果，以便我可以在登录成功或不成功时显示给用户。





我们非常感谢您的帮助。



我尝试过：

使用System; 
使用System.Collections.Generic;使用System.ComponentModel 
; 
使用System.Data;使用System.Drawing 
; 
使用System.Linq; 
使用System.Text; 
使用System.Threading.Tasks; 
使用System.Threading; 
使用System.Windows.Forms; 
使用System.Data.OleDb; 
使用Excel = Microsoft.Office.Interop.Excel; 
使用System.Runtime.InteropServices; 
使用System.Drawing.Printing; 
名称空间LoginDemo 
 {
公共部分类Form1：表格
 {
 
 
公共Form1（）
 {
 InitializeComponent（）; 
} 
 //登录将被取消
 private void btncancel_Click（object sender，EventArgs e）
 {
 if（backgroundWorker1.WorkerSupportsCancellation == true）{
 backgroundWorker1.CancelAsync（）; 
 btnlogin.Enabled = true; 
 btncancel.Enabled = false; 
} 
} 
 //登录将被处理
 private void btnlogin_Click（object sender，EventArgs e）
 {
 
 testobj.username = txtid.Text.Trim（）。ToString（）; 
 if（txtid.Text == string.Empty）
 {
 MessageBox.Show（Please enter username，Login Error，MessageBoxButtons.OK，MessageBoxIcon.Error）; 
 txtid.Focus（）; 
} 
其他
 {
 lblMessage.Visible = true; 
 progressBar1.Visible = true; 
 
 testobj.ReadData（）; 
 backgroundWorker1.RunWorkerAsync（）; 
 btnlogin.Enabled = false; 
 btncancel.Enabled = true; 
 / * if（chckrbm.Checked == true）
 {
 IMACBOX.Properties.Settings.Default.loginUsername = username; 
 IMACBOX.Properties.Settings.Default.Save（）; 
} * / 
 
 // ReadData（connectionString）; 
} 
 
 
 
 
 
 
} 
 //将处理繁重的工作
 private void backgroundWorker1_DoWork（object sender，DoWorkEventArgs e）
 {
 
 int dataload = 0; 
 for（dataload = 0; dataload< = 100; dataload ++）
 {
 if（backgroundWorker1.CancellationPending == true）
 {
 
 / /用户点击取消按钮
 e.Cancel = true; 
 backgroundWorker1.ReportProgress（0）; 
休息; 
} 
 else {
 //做重工
 // ReadDatas（）; 
 // dataload + = 1; 
 // testobj.ReadData（）; 
 backgroundWorker1.ReportProgress（dataload）; //报告进度
} 
} 
 e.Result = dataload; 
} 
 //将在繁重的工作进度上更新进度条
 private void backgroundWorker1_ProgressChanged（object sender，ProgressChangedEventArgs e）
 {
 //更新程序进度条
 
 
 progressBar1.Value = e.ProgressPercentage; 
 lblMessage.Text =Loading ...+ e.ProgressPercentage.ToString（）+％; 
 
} 
 //进度完成时会更新
 private void backgroundWorker1_RunWorkerCompleted（对象发件人，RunWorkerCompletedEventArgs e）
 {
 //显示前检查进度消息
 
 if（e.Cancelled == true）
 {
 MessageBox.Show（Operation Cancelled，Cancelled，MessageBoxButtons.OK，MessageBoxIcon.Information）; 
 progressBar1.Value = 0; //如果用户取消了
 lblMessage.Text =; //重置进度条值//清除标签
 progressBar1.Visible = false; 
} 
 else if（e.Error！= null）
 {
 
 // String somethingwrong = e.Result.ToString（）; 
 MessageBox.Show（e.Error +Error found+ e.Error.Message，Error，MessageBoxButtons.OK，MessageBoxIcon.Error）; 
 progressBar1.Value = 0; //如果用户取消
 lblMessage.Text =; //重置进度条值//清除标签
 
} 
 else {
 MessageBox.Show（已完成进度+ e.Result.ToString（）+，Done，MessageBoxButtons.OK，MessageBoxIcon.Information）; 
 progressBar1.Value = 0; //如果用户取消了
 lblMessage.Text =; //重置进度条值//清除标签
} 
} 
 //执行繁重工作的方法
 private void ReadDatas（）{
 try {
 
 Thread.Sleep（100）; 
 
 
} catch（例外e）{
 
 MessageBox.Show（登录结果，e.Message，MessageBoxButtons.OK，MessageBoxIcon.Information）; 
 progressBar1.Value = 0; //如果用户取消，则重置进度条值
 lblMessage.Text =; //清除标签
} 
} 
 
 
 
 private void Form1_Load（object sender，EventArgs e）
 {
 // username = txtid.Text.Trim（）; 
 // status = lblMessage.Text.ToString（）; 
 // bar = progressBar1.Value; 
} 
} 
} 

使用System; 
使用System.Collections.Generic; 
使用System.Linq; 
使用System.Text; 
使用System.Threading.Tasks; 
使用System.Threading; 
使用System.Windows.Forms; 
使用System.Data.OleDb; 
使用Excel = Microsoft.Office.Interop.Excel; 
使用System.Runtime.InteropServices; 
使用System.Drawing.Printing; 
使用System.Data; 
命名空间LoginDemo 
 {
 class testobj 
 {
 
 public static String username，lastname，firstname，status，lblMessage; 
 public static int progressBar1Value = 0; 
 public static string connectionString = @Provider = Microsoft.ACE.OLEDB.12.0; Data Source = D：\IMAC\APP\IMACDB\FormDB2.xlsx; Extended Properties ='Excel 12.0; HDR =是;'; 
 // public string connectionString = @Provider = Microsoft.ACE.OLEDB.12.0; Data Source = \\132.186.144.184\d $ \FormDB4.xlsx; Extended Properties ='Excel 12.0; HDR =是;'; 
 // public string connectionString = @Provider = Microsoft.ACE.OLEDB.12.0; Data Source = \\132.186.144.239\d $ \IMAC\APP\IMACDB\FormDB2.xlsx ;扩展属性='Excel 12.0; HDR =是;'; 
 public static OleDbConnection cnn; 
 public static OleDbCommand cmd; 
 public static OleDbDataAdapter da; 
 public static OleDbDataReader dr; 
 public DataSet dstResults = new DataSet（）; 
 public DataView myView; 
 public DataTable dtable; 
 public DataColumn c; 
 
 public static void ReadData（）
 {
 
 try 
 {
 
 string queryString =SELECT Employee_ID，LastName， FirstName FROM [Entries $] WHERE Employee_ID ='+ username.Trim（）。ToString（）+'; 
 dr = null; 
 cnn = new OleDbConnection（connectionString）; 
 cmd = new OleDbCommand（queryString，cnn）; 
 cnn.Open（）; 
 dr = cmd.ExecuteReader（）; 
 
 
 
 
 
 if（dr.Read（）== true）
 {
 
线程。睡眠（100）; 
 // MessageBox.Show（进度条）; 
 firstname = dr [1] .ToString（）; 
 lastname = dr [2] .ToString（）; 
 MessageBox.Show（登录成功）; 
 
} 
 else 
 {
 MessageBox.Show（Username Invalid，Error Message）; 
 
} 
 //完成阅读后始终致电关闭。 
 dr.Close（）; 
} 
 //} 
 catch（例外e）
 {
 MessageBox.Show（Error+ e.Message，Error）; 
} 
 
 
} 
} 
} 

解决方案

< blockquote> \FormDB4.xlsx;扩展属性='Excel 12.0; HDR =是;';
//公共字符串connectionString = @Provider = Microsoft.ACE.OLEDB.12.0;数据源= \\\ \\ 132.186.144.239 \d

\IMAC\APP \IMACDB \FormDB2.xlsx;扩展属性='Excel 12.0; HDR =是;';
public static OleDbConnection cnn;
public static OleDbCommand cmd;
public static OleDbDataAdapter da;
public static OleDbDataReader dr;
public DataSet dstResults = new DataSet（）;
public DataView myView;
public DataTable dtable;
public DataColumn c;

public static void ReadData（）
{

try
{

string queryString =SELECT Employee _ID，LastName，FirstName FROM [条目

WHERE Employee_ID ='+ username.Trim（）。ToString（）+';
dr = null;
cnn = new OleDbConnection（connectionString）;
cmd = new OleDbCommand（queryString，cnn）;
cnn.Open（）;
dr = cmd.ExecuteReader（）;





if（dr.Read（）== true）
{

线程。睡眠（100）;
// MessageBox.Show（进度条）;
firstname = dr [1] .ToString（）;
lastname = dr [2] .ToString（）;
MessageBox.Show（登录成功）;

}
else
{
MessageBox.Show（Username Invalid，Error Message）;

}
//完成阅读后始终致电关闭。
dr.Close（）;
}
//}
catch（例外e）
{
MessageBox.Show（Error+ e.Message，Error）;
}


}
}
}

Hi,

Can someone please clarify to me how background worker actually works. I would like to do a simple login form that will show login progress to the user after they click loggin since normally it will take long to read login details therefore I would like to update the user instead of letting the ui hang.

I have tried the code below but I am not sure how or where do I save the result so that I can display to the user if login is successfull or not.


Any assistance will be much appreciated.

What I have tried:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.Windows.Forms;
using System.Data.OleDb;
using Excel = Microsoft.Office.Interop.Excel;
using System.Runtime.InteropServices;
using System.Drawing.Printing;
namespace LoginDemo
{
    public partial class Form1 : Form
    {

    
        public Form1()
        {
            InitializeComponent();
        }
        //Login will be cancelled
        private void btncancel_Click(object sender, EventArgs e)
        {
            if(backgroundWorker1.WorkerSupportsCancellation == true){
                backgroundWorker1.CancelAsync();
                btnlogin.Enabled = true;
                btncancel.Enabled = false;           
            }
        }
        //Login will be processed
        private void btnlogin_Click(object sender, EventArgs e)
        {
        
            testobj.username = txtid.Text.Trim().ToString();
            if (txtid.Text == string.Empty)
            {
                MessageBox.Show("Please enter username", "Login Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                txtid.Focus();
            }
            else
            {
                lblMessage.Visible = true;
                progressBar1.Visible = true;

                testobj.ReadData();
                backgroundWorker1.RunWorkerAsync();
                btnlogin.Enabled = false;
                btncancel.Enabled = true;
              /*  if (chckrbm.Checked == true)
                {
                    IMACBOX.Properties.Settings.Default.loginUsername = username;
                    IMACBOX.Properties.Settings.Default.Save();
                }*/

             //  ReadData(connectionString);
            }
            
            
            
            
          

        }
        // Will handle the heavy work
        private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {

            int dataload = 0;
            for (dataload = 0; dataload <= 100; dataload++)
            {
                if (backgroundWorker1.CancellationPending == true)
                {
                   
                    //user clicked cancel button
                    e.Cancel = true;
                    backgroundWorker1.ReportProgress(0);
                   break;
                }
                else {
                    //do the heavywork
                   // ReadDatas();
                  //  dataload += 1;
                   // testobj.ReadData();
                    backgroundWorker1.ReportProgress(dataload);//Report progress
                }
            }
            e.Result = dataload;
        }
        // Will update progressbar on heavy work progress
        private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            //Updater progress bar

           
            progressBar1.Value = e.ProgressPercentage;
            lblMessage.Text = "Loading..." + e.ProgressPercentage.ToString() + " %";
            
        }
        // Will update when progress is completed
        private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            //Check progress before displaying message

            if (e.Cancelled == true)
            {
                MessageBox.Show("Operation Cancelled ", "Cancelled ", MessageBoxButtons.OK, MessageBoxIcon.Information);
                progressBar1.Value = 0; // Reset progressbar value if user cancelled
                lblMessage.Text = "";//clear the label
                progressBar1.Visible = false;
            }
            else if (e.Error != null)
            {

               // String somethingwrong = e.Result.ToString();
                MessageBox.Show(e.Error + "Error found " + e.Error.Message , "Error ", MessageBoxButtons.OK, MessageBoxIcon.Error);
                progressBar1.Value = 0; // Reset progressbar value if user cancelled
                lblMessage.Text = "";//clear the label

            }
            else {
                MessageBox.Show("Progress done " + e.Result.ToString() + " ","Done ",MessageBoxButtons.OK,MessageBoxIcon.Information);
                progressBar1.Value = 0; // Reset progressbar value if user cancelled
                lblMessage.Text = "";//clear the label
            }
        }
        //Method for doing the heavy work
        private void ReadDatas() {
            try {

                Thread.Sleep(100);


            }catch(Exception e){

                MessageBox.Show("Login Result ", e.Message , MessageBoxButtons.OK,MessageBoxIcon.Information);
                progressBar1.Value = 0; // Reset progressbar value if user cancelled
                lblMessage.Text = "";//clear the label
            }
        }

      

        private void Form1_Load(object sender, EventArgs e)
        {
          //  username = txtid.Text.Trim();
         //   status = lblMessage.Text.ToString();
          //  bar = progressBar1.Value;
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.Windows.Forms;
using System.Data.OleDb;
using Excel = Microsoft.Office.Interop.Excel;
using System.Runtime.InteropServices;
using System.Drawing.Printing;
using System.Data;
namespace LoginDemo
{
    class testobj
    {

        public static String username, lastname, firstname, status, lblMessage;
        public static int progressBar1Value = 0;
        public static string connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\IMAC\APP\IMACDB\FormDB2.xlsx;Extended Properties='Excel 12.0;HDR=Yes;'";
        // public string connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\132.186.144.184\d$\FormDB4.xlsx;Extended Properties='Excel 12.0;HDR=Yes;'";
        //   public string connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\132.186.144.239\d$\IMAC\APP\IMACDB\FormDB2.xlsx;Extended Properties='Excel 12.0;HDR=Yes;'";
        public static OleDbConnection cnn;
        public static OleDbCommand cmd;
        public static OleDbDataAdapter da;
        public static OleDbDataReader dr;
        public DataSet dstResults = new DataSet();
        public DataView myView;
        public DataTable dtable;
        public DataColumn c;
    
     public static  void ReadData()
        {

            try
            {
             
                string queryString = "SELECT Employee_ID,LastName,FirstName FROM [Entries$] WHERE Employee_ID ='" + username.Trim().ToString() + "'";
                dr = null;
                cnn = new OleDbConnection(connectionString);
                cmd = new OleDbCommand(queryString, cnn);
                cnn.Open();
                dr = cmd.ExecuteReader();



            
                
                if (dr.Read() == true)
                {
              
                    Thread.Sleep(100);
                    // MessageBox.Show("Progress bar");
                    firstname = dr[1].ToString();
                    lastname = dr[2].ToString();
                    MessageBox.Show("Login successfull"); 
            
                }
                else
                {
                    MessageBox.Show("Username Invalid", "Error Message");

                }
                // Always call Close when done reading.
                dr.Close();
            }
            //  }
            catch (Exception e)
            {
                MessageBox.Show("Error " + e.Message, "Error");
            }
         

       }
    }
}

解决方案

\FormDB4.xlsx;Extended Properties='Excel 12.0;HDR=Yes;'"; // public string connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\132.186.144.239\d

\IMAC\APP\IMACDB\FormDB2.xlsx;Extended Properties='Excel 12.0;HDR=Yes;'"; public static OleDbConnection cnn; public static OleDbCommand cmd; public static OleDbDataAdapter da; public static OleDbDataReader dr; public DataSet dstResults = new DataSet(); public DataView myView; public DataTable dtable; public DataColumn c; public static void ReadData() { try { string queryString = "SELECT Employee_ID,LastName,FirstName FROM [Entries

WHERE Employee_ID ='" + username.Trim().ToString() + "'"; dr = null; cnn = new OleDbConnection(connectionString); cmd = new OleDbCommand(queryString, cnn); cnn.Open(); dr = cmd.ExecuteReader(); if (dr.Read() == true) { Thread.Sleep(100); // MessageBox.Show("Progress bar"); firstname = dr[1].ToString(); lastname = dr[2].ToString(); MessageBox.Show("Login successfull"); } else { MessageBox.Show("Username Invalid", "Error Message"); } // Always call Close when done reading. dr.Close(); } // } catch (Exception e) { MessageBox.Show("Error " + e.Message, "Error"); } } } }

这篇关于如何使用后台工作者+进度条进行C＃登录的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！