BackgroundWork類使用DEMO

BackgroundWork類使用DEMO

using System; using System.Collections; using System.ComponentModel; using System.Drawing; using System.Threading; using System.Windows.Forms;

namespace BackgroundWorkerExample {      public class FibonacciForm : System.Windows.Forms.Form      {          private int numberToCompute = 0;          private int highestPercentageReached = 0;

         private System.Windows.Forms.NumericUpDown numericUpDown1;          private System.Windows.Forms.Button startAsyncButton;          private System.Windows.Forms.Button cancelAsyncButton;          private System.Windows.Forms.ProgressBar progressBar1;          private System.Windows.Forms.Label resultLabel;          private System.ComponentModel.BackgroundWorker backgroundWorker1;                   public FibonacciForm()          {              InitializeComponent();              InitializeBackgoundWorker();          }          private void InitializeBackgoundWorker()          {              backgroundWorker1.DoWork +=   new DoWorkEventHandler(backgroundWorker1_DoWork);              backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);              backgroundWorker1.ProgressChanged +=new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);          }          private void startAsyncButton_Click(System.Object sender, System.EventArgs e)          {              resultLabel.Text = String.Empty;              this.numericUpDown1.Enabled = false;              this.startAsyncButton.Enabled = false;              this.cancelAsyncButton.Enabled = true;              numberToCompute = (int)numericUpDown1.Value;              highestPercentageReached = 0;              backgroundWorker1.RunWorkerAsync(numberToCompute);          }          private void cancelAsyncButton_Click(System.Object sender,System.EventArgs e)          {              this.backgroundWorker1.CancelAsync();              cancelAsyncButton.Enabled = false;          }          private void backgroundWorker1_DoWork(object sender,DoWorkEventArgs e)          {              BackgroundWorker worker = sender as BackgroundWorker;              e.Result = Sum((int)e.Argument, worker, e);          }          private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)          {              if (e.Error != null)              {                  MessageBox.Show(e.Error.Message);              }              else if (e.Cancelled)              {                  resultLabel.Text = "Canceled";              }              else              {                  resultLabel.Text = e.Result.ToString();              }              this.numericUpDown1.Enabled = true;              startAsyncButton.Enabled = true;              cancelAsyncButton.Enabled = false;          }          private void backgroundWorker1_ProgressChanged(object sender,ProgressChangedEventArgs e)          {              this.progressBar1.Value = e.ProgressPercentage;          }          long Sum(int n, BackgroundWorker worker, DoWorkEventArgs e)          {              long result = 0;              if (worker.CancellationPending)              {                  e.Cancel = true;              }              else              {                  for (int i = 1; i <= n; i++)                  {                      result = result + i;                  int percentComplete =(int)((float)i / (float)numberToCompute * 100);                  if (percentComplete > highestPercentageReached)                  {                      highestPercentageReached = percentComplete;                      worker.ReportProgress(percentComplete);                  }                  }              }

             return result;          }          #region Windows Form Designer generated code

         private void InitializeComponent()          {              this.numericUpDown1 = new System.Windows.Forms.NumericUpDown();              this.startAsyncButton = new System.Windows.Forms.Button();              this.cancelAsyncButton = new System.Windows.Forms.Button();              this.resultLabel = new System.Windows.Forms.Label();              this.progressBar1 = new System.Windows.Forms.ProgressBar();              this.backgroundWorker1 = new System.ComponentModel.BackgroundWorker();              ((System.ComponentModel.ISupportInitialize)(this.numericUpDown1)).BeginInit();              this.SuspendLayout();              //              // numericUpDown1              //              this.numericUpDown1.Location = new System.Drawing.Point(16, 16);              this.numericUpDown1.Maximum = new decimal(new int[] {              1215752191,              23,              0,              0});              this.numericUpDown1.Minimum = new decimal(new int[] {              1,              0,              0,              0});              this.numericUpDown1.Name = "numericUpDown1";              this.numericUpDown1.Size = new System.Drawing.Size(80, 21);              this.numericUpDown1.TabIndex = 0;              this.numericUpDown1.Value = new decimal(new int[] {              10,              0,              0,              0});              //              // startAsyncButton              //              this.startAsyncButton.Location = new System.Drawing.Point(18, 64);              this.startAsyncButton.Name = "startAsyncButton";              this.startAsyncButton.Size = new System.Drawing.Size(120, 23);              this.startAsyncButton.TabIndex = 1;              this.startAsyncButton.Text = "Start Async";              this.startAsyncButton.Click += new System.EventHandler(this.startAsyncButton_Click);              //              // cancelAsyncButton              //              this.cancelAsyncButton.Enabled = false;              this.cancelAsyncButton.Location = new System.Drawing.Point(155, 64);              this.cancelAsyncButton.Name = "cancelAsyncButton";              this.cancelAsyncButton.Size = new System.Drawing.Size(119, 23);              this.cancelAsyncButton.TabIndex = 2;              this.cancelAsyncButton.Text = "Cancel Async";              this.cancelAsyncButton.Click += new System.EventHandler(this.cancelAsyncButton_Click);              //              // resultLabel              //              this.resultLabel.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;              this.resultLabel.Location = new System.Drawing.Point(112, 16);              this.resultLabel.Name = "resultLabel";              this.resultLabel.Size = new System.Drawing.Size(160, 23);              this.resultLabel.TabIndex = 3;              this.resultLabel.Text = "(no result)";              this.resultLabel.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;              //              // progressBar1              //              this.progressBar1.Location = new System.Drawing.Point(18, 48);              this.progressBar1.Name = "progressBar1";              this.progressBar1.Size = new System.Drawing.Size(256, 10);              this.progressBar1.Step = 2;              this.progressBar1.TabIndex = 4;              //              // backgroundWorker1              //              this.backgroundWorker1.WorkerReportsProgress = true;              this.backgroundWorker1.WorkerSupportsCancellation = true;              //              // FibonacciForm              //              this.ClientSize = new System.Drawing.Size(292, 107);              this.Controls.Add(this.progressBar1);              this.Controls.Add(this.resultLabel);              this.Controls.Add(this.cancelAsyncButton);              this.Controls.Add(this.startAsyncButton);              this.Controls.Add(this.numericUpDown1);              this.Name = "FibonacciForm";              this.Text = "Sum";              this.Load += new System.EventHandler(this.FibonacciForm_Load);              ((System.ComponentModel.ISupportInitialize)(this.numericUpDown1)).EndInit();              this.ResumeLayout(false);

         }          #endregion          [STAThread]          static void Main()          {              Application.Run(new FibonacciForm());          }

         private void FibonacciForm_Load(object sender, EventArgs e)          {

         }      } }