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CheckForUpdateCompletedEventArgs Class

Represents detailed update information obtained through a call to CheckForUpdateAsync.

System.Object
  System.EventArgs
    System.ComponentModel.AsyncCompletedEventArgs
      System.Deployment.Application.CheckForUpdateCompletedEventArgs

Namespace:  System.Deployment.Application
Assembly:  System.Deployment (in System.Deployment.dll)

'Declaration
Public Class CheckForUpdateCompletedEventArgs _
	Inherits AsyncCompletedEventArgs

The CheckForUpdateCompletedEventArgs type exposes the following members.

  NameDescription
Public propertyAvailableVersionGets the version number of the latest uninstalled version.
Public propertyCancelledGets a value indicating whether an asynchronous operation has been canceled. (Inherited from AsyncCompletedEventArgs.)
Public propertyErrorGets a value indicating which error occurred during an asynchronous operation. (Inherited from AsyncCompletedEventArgs.)
Public propertyIsUpdateRequiredGets a value indicating whether the update must be installed.
Public propertyMinimumRequiredVersionGets the minimum version that the user must have installed on the computer.
Public propertyUpdateAvailableGets whether an uninstalled update is available.
Public propertyUpdateSizeBytesGets the size of the available update.
Public propertyUserStateGets the unique identifier for the asynchronous task. (Inherited from AsyncCompletedEventArgs.)
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  NameDescription
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Protected methodRaiseExceptionIfNecessaryRaises a user-supplied exception if an asynchronous operation failed. (Inherited from AsyncCompletedEventArgs.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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With CheckForUpdateCompletedEventArgs, you can decide whether to upgrade your ClickOnce application based on information about the newest version. UpdateAvailable will return a Boolean value indicating whether there is a new update at all. The AvailableVersion property provides the version number of the new version, while MinimumRequiredVersion provides the earliest version that the user should have installed on the computer. IsUpdateRequired expresses whether the latest available update is required of the user. Finally, UpdateSizeBytes expresses the total size of the update.

The following code example uses UpdateAvailable to determine if there is a new application update, and IsUpdateRequired to determine whether to ask the user to install the update.

Private sizeOfUpdate As Long = 0

Dim WithEvents ADUpdateAsync As ApplicationDeployment

Private Sub UpdateApplication()
    If (ApplicationDeployment.IsNetworkDeployed) Then
        ADUpdateAsync = ApplicationDeployment.CurrentDeployment

        ADUpdateAsync.CheckForUpdateAsync()
    End If 
End Sub 

Private Sub ADUpdateAsync_CheckForUpdateProgressChanged(ByVal sender As Object, ByVal e As DeploymentProgressChangedEventArgs) Handles ADUpdateAsync.CheckForUpdateProgressChanged
    DownloadStatus.Text = [String].Format("{0:D}K of {1:D}K downloaded.", e.BytesCompleted / 1024, e.BytesTotal / 1024)
End Sub 


Private Sub ADUpdateAsync_CheckForUpdateCompleted(ByVal sender As Object, ByVal e As CheckForUpdateCompletedEventArgs) Handles ADUpdateAsync.CheckForUpdateCompleted
    If (e.Error IsNot Nothing) Then
        MessageBox.Show(("ERROR: Could not retrieve new version of the application. Reason: " + ControlChars.Lf + e.Error.Message + ControlChars.Lf + "Please report this error to the system administrator."))
        Return 
    Else 
        If (e.Cancelled = True) Then
            MessageBox.Show("The update was cancelled.")
        End If 
    End If 

    ' Ask the user if they would like to update the application now. 
    If (e.UpdateAvailable) Then
        sizeOfUpdate = e.UpdateSizeBytes

        If (Not e.IsUpdateRequired) Then 
            Dim dr As DialogResult = MessageBox.Show("An update is available. Would you like to update the application now?", "Update Available", MessageBoxButtons.OKCancel)
            If (System.Windows.Forms.DialogResult.OK = dr) Then
                BeginUpdate()
            End If 
        Else
            MessageBox.Show("A mandatory update is available for your application. We will install the update now, after which we will save all of your in-progress data and restart your application.")
            BeginUpdate()
        End If 
    End If 
End Sub 

Private Sub BeginUpdate()
    ADUpdateAsync = ApplicationDeployment.CurrentDeployment
    ADUpdateAsync.UpdateAsync()
End Sub 


Private Sub ADUpdateAsync_UpdateProgressChanged(ByVal sender As Object, ByVal e As DeploymentProgressChangedEventArgs) Handles ADUpdateAsync.UpdateProgressChanged
    Dim progressText As String = String.Format("{0:D}K out of {1:D}K downloaded - {2:D}% complete", e.BytesCompleted / 1024, e.BytesTotal / 1024, e.ProgressPercentage)
    DownloadStatus.Text = progressText
End Sub 


Private Sub ADUpdateAsync_UpdateCompleted(ByVal sender As Object, ByVal e As AsyncCompletedEventArgs) Handles ADUpdateAsync.UpdateCompleted
    If (e.Cancelled) Then
        MessageBox.Show("The update of the application's latest version was cancelled.")
        Exit Sub 
    Else 
        If (e.Error IsNot Nothing) Then
            MessageBox.Show("ERROR: Could not install the latest version of the application. Reason: " + ControlChars.Lf + e.Error.Message + ControlChars.Lf + "Please report this error to the system administrator.")
            Exit Sub 
        End If 
    End If 

    Dim dr As DialogResult = MessageBox.Show("The application has been updated. Restart? (If you do not restart now, the new version will not take effect until after you quit and launch the application again.)", "Restart Application", MessageBoxButtons.OKCancel)
    If (dr = System.Windows.Forms.DialogResult.OK) Then
        Application.Restart()
    End If 
End Sub

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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