DownloadProgressChangedEventArgs Class


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Provides data for the DownloadProgressChanged event.

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


Public Class DownloadProgressChangedEventArgs
	Inherits ProgressChangedEventArgs


Gets the number of bytes downloaded to the local computer.


Gets the asynchronous task progress percentage.(Inherited from ProgressChangedEventArgs.)


Gets the progress state of the download.


Gets the total number of bytes for the download operation.


Gets a unique user state.(Inherited from ProgressChangedEventArgs.)


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Creates a shallow copy of the current Object.(Inherited from Object.)


Returns a string that represents the current object.(Inherited from Object.)

In a console application, since events are assigned to threads out of a thread pool, you might receive update progress events out of order, with a subsequent event showing a decrease compared to a previous event. You will not see such behavior in a Windows Forms application, because events in Windows Forms are processed sequentially out of the UI thread's message queue.

The following code example demonstrates the use of DownloadProgressChangedEventArgs in the context of an application that uses InPlaceHostingManager to download and install a ClickOnce application programmatically.

    Dim WithEvents iphm As InPlaceHostingManager = Nothing

    Public Sub InstallApplication(ByVal deployManifestUriStr As String)
            Dim deploymentUri As New Uri(deployManifestUriStr)
            iphm = New InPlaceHostingManager(deploymentUri, False)
            MessageBox.Show("Created the object.")
        Catch uriEx As UriFormatException
            MessageBox.Show("Cannot install the application: " & _
                            "The deployment manifest URL supplied is not a valid URL." & _
                            "Error: " & uriEx.Message)
        Catch platformEx As PlatformNotSupportedException
            MessageBox.Show("Cannot install the application: " & _
                            "This program requires Windows XP or higher. " & _
                            "Error: " & platformEx.Message)
        Catch argumentEx As ArgumentException
            MessageBox.Show("Cannot install the application: " & _
                            "The deployment manifest URL supplied is not a valid URL." & _
                            "Error: " & argumentEx.Message)
        End Try

    End Sub

    Private Sub iphm_GetManifestCompleted(ByVal sender As Object, ByVal e As GetManifestCompletedEventArgs) Handles iphm.GetManifestCompleted
        ' Check for an error.
        If (e.Error IsNot Nothing) Then
            ' Cancel download and install.
            MessageBox.Show("Could not download manifest. Error: " & e.Error.Message)
        End If

        ' Dim isFullTrust As Boolean = CheckForFullTrust(e.ApplicationManifest)

        ' Verify this application can be installed.
            ' the true parameter allows InPlaceHostingManager
            ' to grant the permissions requested in the application manifest. 
        Catch ex As Exception
            MessageBox.Show("An error occurred while verifying the application. " & _
                            "Error text: " & ex.Message)
        End Try

        ' Use the information from GetManifestCompleted() to confirm 
        ' that the user wants to proceed.
        Dim appInfo As String = "Application Name: " & e.ProductName
        appInfo &= ControlChars.Lf & "Version: " & e.Version.ToString()
        appInfo &= ControlChars.Lf & "Support/Help Requests: "

        If Not (e.SupportUri Is Nothing) Then
            appInfo &= e.SupportUri.ToString()
            appInfo &= "N/A"
        End If

        appInfo &= ControlChars.Lf & ControlChars.Lf & _
            "Confirmed that this application can run with its requested permissions."

        ' If isFullTrust Then
        '    appInfo &= ControlChars.Lf & ControlChars.Lf & _
        '        "This application requires full trust in order to run."
        ' End If

        appInfo &= ControlChars.Lf & ControlChars.Lf & "Proceed with installation?"

        Dim dr As DialogResult = MessageBox.Show(appInfo, _
            "Confirm Application Install", MessageBoxButtons.OKCancel, MessageBoxIcon.Question)
        If dr <> System.Windows.Forms.DialogResult.OK Then
        End If

        ' Download the deployment manifest. 
        ' Usually, this shouldn't throw an exception unless 
        ' AssertApplicationRequirements() failed, or you did not call that method
        ' before calling this one.
        Catch downloadEx As Exception
            MessageBox.Show("Cannot initiate download of application. Error: " & downloadEx.Message)
        End Try
    End Sub

#If 0 Then
    Private Function CheckForFullTrust(ByVal appManifest As XmlReader) As Boolean
        Dim isFullTrust As Boolean = False

        If (appManifest Is Nothing) Then
            Throw New ArgumentNullException("appManifest cannot be null.")
        End If

        Dim xaUnrestricted As XAttribute
        xaUnrestricted = XDocument.Load(appManifest) _
            .Element("{urn:schemas-microsoft-com:asm.v1}assembly") _
            .Element("{urn:schemas-microsoft-com:asm.v2}trustInfo") _
            .Element("{urn:schemas-microsoft-com:asm.v2}security") _
            .Element("{urn:schemas-microsoft-com:asm.v2}applicationRequestMinimum") _
            .Element("{urn:schemas-microsoft-com:asm.v2}PermissionSet") _
            .Attribute("Unrestricted")  ' Attributes never have a namespace

        If xaUnrestricted Then
            If xaUnrestricted.Value = "true" Then
                Return True
            End If
        End If

        Return False
    End Function
#End If

    Private Sub iphm_DownloadProgressChanged(ByVal sender As Object, ByVal e As DownloadProgressChangedEventArgs) Handles iphm.DownloadProgressChanged
        ' you can show percentage of task completed using e.ProgressPercentage
    End Sub

    Private Sub iphm_DownloadApplicationCompleted(ByVal sender As Object, ByVal e As DownloadApplicationCompletedEventArgs) Handles iphm.DownloadApplicationCompleted
        ' Check for an error.
        If (e.Error IsNot Nothing) Then
            ' Cancel download and install.
            MessageBox.Show("Could not download and install application. Error: " & e.Error.Message)
        End If

        ' Inform the user that their application is ready for use. 
        MessageBox.Show("Application installed! You may now run it from the Start menu.")
    End Sub

.NET Framework
Available since 2.0

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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