Use BackgroundWorker to run task at background : BackgroundWorker « Windows Presentation Foundation « VB.Net Tutorial

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VB.Net Tutorial » Windows Presentation Foundation » BackgroundWorker 
16.114.1.Use BackgroundWorker to run task at background
<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="WPF" Height="100" Width="200">
    <StackPanel>
        <ProgressBar Name="progressBar" Margin="4"/>
        <Button Name="button" Click="button_Click">Start</Button>
    </StackPanel>
</Window>

//File:Window.xaml.vb
Imports System.ComponentModel
Imports System.Threading
Imports System.Windows
Imports System.Windows.Input

Namespace WpfApplication1
  Public Partial Class Window1
    Inherits Window
    Private worker As New BackgroundWorker()

    Public Sub New()
      InitializeComponent()
      worker.WorkerReportsProgress = True
      AddHandler worker.DoWork, New DoWorkEventHandler(AddressOf worker_DoWork)
      AddHandler worker.RunWorkerCompleted, New RunWorkerCompletedEventHandler(AddressOf worker_RunWorkerCompleted)
      AddHandler worker.ProgressChanged, AddressOf worker_ProgressChanged
    End Sub

    Private Sub button_Click(sender As Object, e As RoutedEventArgs)
      worker.RunWorkerAsync()
      Me.Cursor = Cursors.Wait
      button.IsEnabled = False
    End Sub

    Private Sub worker_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs)
      Me.Cursor = Cursors.Arrow
      If e.[ErrorIsNot Nothing Then
        MessageBox.Show(e.[Error].Message)
      End If
      button.IsEnabled = True
    End Sub
    Private Sub worker_DoWork(sender As Object, e As DoWorkEventArgs)
      For i As Integer = To 100
        Thread.Sleep(100)
        worker.ReportProgress(i)
      Next
    End Sub

    Private Sub worker_ProgressChanged(sender As Object, e As ProgressChangedEventArgs)
      progressBar.Value = e.ProgressPercentage
    End Sub
  End Class
End Namespace
WPF Use Background Worker To Run Task At Background
16.114.BackgroundWorker
16.114.1.Use BackgroundWorker to run task at backgroundUse BackgroundWorker to run task at background
16.114.2.Using a BackgroundWorker: progress changed and completedUsing a BackgroundWorker: progress changed and completed
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