ToolStripProgressBar Class

Represents a Windows progress bar control contained in a StatusStrip.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

'Declaration
Public Class ToolStripProgressBar
	Inherits ToolStripControlHost
'Usage
Dim instance As ToolStripProgressBar

public class ToolStripProgressBar extends ToolStripControlHost
public class ToolStripProgressBar extends ToolStripControlHost
Not applicable.

ToolStripProgressBar is the ProgressBar optimized for hosting in a ToolStrip. A subset of the hosted control's properties and events are exposed at the ToolStripProgressBar level, but the underlying ProgressBar control is fully accessible through the ProgressBar property.

A ToolStripProgressBar control visually indicates the progress of a lengthy operation. The ToolStripProgressBar control displays a bar that fills in from left to right with the system highlight color as an operation progresses.

NoteNote:

The ToolStripProgressBar control can only be oriented horizontally.

The ToolStripProgressBar control is typically used when an application performs tasks such as copying files or printing documents. Users of an application might consider an application unresponsive if there is no visual cue. Use the ToolStripProgressBar to notify the user that the application is performing a lengthy task and that the application is still responding.

The Maximum and Minimum properties define the range of values to represent the progress of a task. The Minimum property is typically set to a value of zero, and the Maximum property is typically set to a value indicating the completion of a task. For example, to display the progress properly when copying a group of files, the Maximum property could be set to the total number of files to be copied. The Value property represents the progress that the application has made toward completing the operation. Because the bar displayed in the control is a collection of blocks, the value displayed by the ToolStripProgressBar only approximates the Value property's current value. Based on the size of the ToolStripProgressBar, the Value property determines when to display the next block.

There are a number of ways to modify the value displayed by the ToolStripProgressBar other than changing the Value property directly. You can use the Step property to specify a specific value to increment the Value property by, and then call the PerformStep method to increment the value. To vary the increment value, you can use the Increment method and specify a value by which to increment the Value property.

ToolStripProgressBar replaces the older ProgressBar control, which is nevertheless retained for backward compatibility.

The following code example demonstrates a ToolStripProgressBar that calculates a sequence of Fibonacci numbers.

Imports System
Imports System.Collections.Generic
Imports System.Windows.Forms
Imports System.ComponentModel



Class FibonacciNumber
   Inherits Form
   
   <STAThread()>  _
   Shared Sub Main()
      Application.EnableVisualStyles()
      Application.Run(New FibonacciNumber())
   End Sub    
   Private progressStatusStrip As StatusStrip
   Private toolStripProgressBar As ToolStripProgressBar
   Private requestedCountControl As NumericUpDown
   Private goButton As Button
   Private outputTextBox As TextBox
   Private backgroundWorker As BackgroundWorker
   Private toolStripStatusLabel As ToolStripStatusLabel
   Private requestedCount As Integer
   
   
   Public Sub New()
      [Text] = "Fibonacci"
      
      ' Prepare the StatusStrip.
      progressStatusStrip = New StatusStrip()
      toolStripProgressBar = New ToolStripProgressBar()
      toolStripProgressBar.Enabled = False
      toolStripStatusLabel = New ToolStripStatusLabel()
      progressStatusStrip.Items.Add(toolStripProgressBar)
      progressStatusStrip.Items.Add(toolStripStatusLabel)
      
      Dim flp As New FlowLayoutPanel()
      flp.Dock = DockStyle.Top
      
      Dim beforeLabel As New Label()
      beforeLabel.Text = "Calculate the first "
      beforeLabel.AutoSize = True
      flp.Controls.Add(beforeLabel)
      requestedCountControl = New NumericUpDown()
      requestedCountControl.Maximum = 1000
      requestedCountControl.Minimum = 1
      requestedCountControl.Value = 100
      flp.Controls.Add(requestedCountControl)
      Dim afterLabel As New Label()
      afterLabel.Text = "Numbers in the Fibonacci sequence."
      afterLabel.AutoSize = True
      flp.Controls.Add(afterLabel)
      
      goButton = New Button()
      goButton.Text = "&Go"
      AddHandler goButton.Click, AddressOf button1_Click
      flp.Controls.Add(goButton)
      
      outputTextBox = New TextBox()
      outputTextBox.Multiline = True
      outputTextBox.ReadOnly = True
      outputTextBox.ScrollBars = ScrollBars.Vertical
      outputTextBox.Dock = DockStyle.Fill
      
      Controls.Add(outputTextBox)
      Controls.Add(progressStatusStrip)
      Controls.Add(flp)
      
      backgroundWorker = New BackgroundWorker()
      backgroundWorker.WorkerReportsProgress = True
      AddHandler backgroundWorker.DoWork, AddressOf backgroundWorker1_DoWork
      AddHandler backgroundWorker.RunWorkerCompleted, AddressOf backgroundWorker1_RunWorkerCompleted
      AddHandler backgroundWorker.ProgressChanged, AddressOf backgroundWorker1_ProgressChanged
   End Sub 
    
   
   Private Sub backgroundWorker1_DoWork(sender As Object, e As DoWorkEventArgs)
      ' This method will run on a thread other than the UI thread.
      ' Be sure not to manipulate any Windows Forms controls created
      ' on the UI thread from this method.
      backgroundWorker.ReportProgress(0, "Working...")
      Dim lastlast As [Decimal] = 0
      Dim last As [Decimal] = 1
      Dim current As [Decimal]
      If requestedCount >= 1 Then
         AppendNumber(0)
      End If
      If requestedCount >= 2 Then
         AppendNumber(1)
      End If
      Dim i As Integer
      
      While i < requestedCount
         ' Calculate the number.
         current = lastlast + last
         ' Introduce some delay to simulate a more complicated calculation.
         System.Threading.Thread.Sleep(100)
         AppendNumber(current)
         backgroundWorker.ReportProgress(100 * i / requestedCount, "Working...")
         ' Get ready for the next iteration.
         lastlast = last
         last = current
         i += 1
      End While
      
      
      backgroundWorker.ReportProgress(100, "Complete!")
    End Sub
   
   
   Delegate Sub AppendNumberDelegate(number As [Decimal])
   
   Private Sub AppendNumber(number As [Decimal])
      If outputTextBox.InvokeRequired Then
         outputTextBox.Invoke(New AppendNumberDelegate(AddressOf AppendNumber), number)
      Else
         outputTextBox.AppendText((number.ToString("N0") + Environment.NewLine))
      End If
   End Sub 
   Private Sub backgroundWorker1_ProgressChanged(sender As Object, e As ProgressChangedEventArgs)
      toolStripProgressBar.Value = e.ProgressPercentage
      toolStripStatusLabel.Text = e.UserState '
   End Sub 
   
   
   Private Sub backgroundWorker1_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs)
      If TypeOf e.Error Is OverflowException Then
         outputTextBox.AppendText((Environment.NewLine + "**OVERFLOW ERROR, number is too large to be represented by the decimal data type**"))
      End If
      toolStripProgressBar.Enabled = False
      requestedCountControl.Enabled = True
      goButton.Enabled = True
   End Sub 
    
   
   Private Sub button1_Click(sender As Object, e As EventArgs)
      goButton.Enabled = False
      toolStripProgressBar.Enabled = True
      requestedCount = Fix(requestedCountControl.Value)
      requestedCountControl.Enabled = False
      outputTextBox.Clear()
      backgroundWorker.RunWorkerAsync()
   End Sub 
End Class 

System.Object
   System.MarshalByRefObject
     System.ComponentModel.Component
       System.Windows.Forms.ToolStripItem
         System.Windows.Forms.ToolStripControlHost
          System.Windows.Forms.ToolStripProgressBar

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0
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