My.Computer.Network.DownloadFile Method

Downloads the specified remote file and saves it in the specified location.

' Usage
My.Computer.Network.DownloadFile(address ,destinationFileName)
My.Computer.Network.DownloadFile(address ,destinationFileName)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password ,showUI ,connectionTimeout ,overwrite)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password ,showUI ,connectionTimeout ,overwrite ,onUserCancel)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password ,showUI ,connectionTimeout ,overwrite)
My.Computer.Network.DownloadFile(address ,destinationFileName ,userName ,password ,showUI ,connectionTimeout ,overwrite ,onUserCancel)
My.Computer.Network.DownloadFile(address ,destinationFileName ,networkCredentials ,showUI ,connectionTimeout ,overwrite)
My.Computer.Network.DownloadFile(address ,destinationFileName ,networkCredentials ,showUI ,connectionTimeout ,overwrite ,onUserCancel)
' Declaration
Public Sub DownloadFile( _
   ByVal address As String, _
   ByVal destinationFileName As String _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As String, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As String, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As String, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean, _
   ByVal onUserCancel As UICancelOption _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String, _
   ByVal userName As String, _
   ByVal password As String, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean, _
   ByVal onUserCancel As UICancelOption _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String, _
   ByVal networkCredentials As System.Net.ICredentials, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean _
)
' -or-
Public Sub DownloadFile( _
   ByVal address As System.Uri, _
   ByVal destinationFileName As String, _
   ByVal networkCredentials As System.Net.ICredentials, _
   ByVal showUI As Boolean, _
   ByVal connectionTimeout As Integer, _
   ByVal overwrite As Boolean, _
   ByVal onUserCancel As UICancelOption _
)

Parameters

• address
  String or Uri. Path of the file to download, including file name and host address. Required.

• destinationFileName
  String. File name and path of the downloaded file. Required.

• userName
  String. User name to authenticate. Default is an empty string, "".

• password
  String.Password to authenticate. Default is an empty string, "".

• showUI
  Boolean. Specifies whether to display the progress of the operation. Default is False.

• connectionTimeout
  Int32. Timeout interval, in milliseconds. Default is 100 seconds.

• overwrite
  Boolean. Specifies whether to overwrite existing files. Default is False.

• onUserCancel
  UICancelOption. Specifies behavior when the user clicks Cancel or No on the dialog box shown as a result of ShowUI set to True. Default is ThrowException.

• networkCredentials
  ICredentials. Credentials to be supplied.

Exceptions

The following conditions may cause an exception to be thrown:

• The drive name is not valid (ArgumentException).

• destinationFileName ends with a trailing slash (ArgumentException).

• overwrite is set to False and the destination file already exists (IOException).

• The server does not respond within the specified connectionTimeout (TimeoutException).

• The authentication fails (SecurityException).

• User lacks necessary permissions (SecurityException).

• The request is denied by the website (WebException).

Remarks

If showUI is set to True, a dialog box appears that shows the progress of the operation; the dialog box contains a Cancel button that can be used to cancel the operation. The dialog box is not modal, and therefore does not block user input to other windows in the program.

If the server does not respond within the specified connectionTimeout, the operation is cancelled, and an exception is thrown.

DownloadFile outputs trace information when you enable network tracing in your application. For more information, see Enabling Network Tracing.

Security Note:
The FTP protocol sends information, including passwords, in plain text and should not be used for transmitting sensitive information.

Tasks

The following table lists an example of a task involving the My.Computer.Network.DownloadFile method.

Example

This example downloads the file WineList.txt from http://www.cohowinery.com/downloads and saves it to C:\Documents and Settings\All Users\Documents.

My.Computer.Network.DownloadFile _
("http://www.cohowinery.com/downloads/WineList.txt", _
"C:\Documents and Settings\All Users\Documents\WineList.txt")

This example downloads the file WineList.txt from http://www.cohowinery.com/downloads and saves it to C:\Documents and Settings\All Users\Documents, specifying a timeout interval of 500 milliseconds.

My.Computer.Network.DownloadFile _
("http://www.cohowinery.com/downloads/", _
"C:\Documents and Settings\All Users\Documents\WineList.txt", _
"", "", False, 500, True)

Requirements

Namespace:Microsoft.VisualBasic.Devices

Class:Network

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

Availability by Project Type

Permissions

The following permissions may be necessary:

For more information, see Code Access Security and Requesting Permissions.

See Also

Tasks

How to: Download a File in Visual Basic

How to: Determine if a Remote Computer is Available in Visual Basic

How to: Parse File Paths in Visual Basic

Reference

My.Computer.Network Object

System.Uri

System.Net.ICredentials

Network.DownloadFile