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' Licensed to the .NET Foundation under one or more agreements.
' The .NET Foundation licenses this file to you under the MIT license.
Imports NetInfoAlias = System.Net.NetworkInformation
Imports VbUtils = Microsoft.VisualBasic.CompilerServices.ExceptionUtils
Namespace Microsoft.VisualBasic.Devices
Partial Public Class Network
'Size of Ping.exe buffer
Private Const BUFFER_SIZE As Integer = 32
' Default timeout for Ping
Private Const DEFAULT_PING_TIMEOUT As Integer = 1000
'Holds the buffer for pinging. We lazy initialize on first use
Private _pingBuffer() As Byte
''' <summary>
''' A buffer for pinging. This imitates the buffer used by Ping.Exe.
''' </summary>
''' <value>A buffer.</value>
Private ReadOnly Property PingBuffer() As Byte()
Get
If _pingBuffer Is Nothing Then
ReDim _pingBuffer(BUFFER_SIZE - 1)
For i As Integer = 0 To BUFFER_SIZE - 1
'This is the same logic Ping.exe uses to fill it's buffer
Dim provider As Globalization.CultureInfo = Globalization.CultureInfo.InvariantCulture
_pingBuffer(i) = Convert.ToByte(Asc("a"c) + (i Mod 23), provider)
Next
End If
Return _pingBuffer
End Get
End Property
''' <summary>
''' Sends and receives a packet to and from the passed in address.
''' </summary>
''' <param name="hostNameOrAddress"></param>
''' <returns>True if ping was successful, otherwise False.</returns>
Public Function Ping(hostNameOrAddress As String) As Boolean
Return Ping(hostNameOrAddress, DEFAULT_PING_TIMEOUT)
End Function
''' <summary>
''' Sends and receives a packet to and from the passed in Uri.
''' </summary>
''' <param name="address">A Uri representing the host.</param>
''' <returns>True if ping was successful, otherwise False.</returns>
Public Function Ping(address As Uri) As Boolean
' We're safe from Ping(Nothing, ...) due to overload failure (Ping(String,...) vs. Ping(Uri,...)).
' However, it is good practice to verify address before calling address.Host.
If address Is Nothing Then
Throw VbUtils.GetArgumentNullException(NameOf(address))
End If
Return Ping(address.Host, DEFAULT_PING_TIMEOUT)
End Function
''' <summary>
''' Sends and receives a packet to and from the passed in address.
''' </summary>
''' <param name="hostNameOrAddress">The name of the host as a Url or IP Address.</param>
''' <param name="timeout">Time to wait before aborting ping.</param>
''' <returns>True if ping was successful, otherwise False.</returns>
Public Function Ping(hostNameOrAddress As String, timeout As Integer) As Boolean
' Make sure a network is available
If Not IsAvailable Then
Throw VbUtils.GetInvalidOperationException(SR.Network_NetworkNotAvailable)
End If
Dim pingMaker As New NetInfoAlias.Ping
Dim reply As NetInfoAlias.PingReply = pingMaker.Send(
hostNameOrAddress,
timeout,
PingBuffer)
If reply.Status = NetInfoAlias.IPStatus.Success Then
Return True
End If
Return False
End Function
''' <summary>
''' Sends and receives a packet to and from the passed in Uri.
''' </summary>
''' <param name="address">A Uri representing the host.</param>
''' <param name="timeout">Time to wait before aborting ping.</param>
''' <returns>True if ping was successful, otherwise False.</returns>
Public Function Ping(address As Uri, timeout As Integer) As Boolean
' We're safe from Ping(Nothing, ...) due to overload failure (Ping(String,...) vs. Ping(Uri,...)).
' However, it is good practice to verify address before calling address.Host.
If address Is Nothing Then
Throw VbUtils.GetArgumentNullException(NameOf(address))
End If
Return Ping(address.Host, timeout)
End Function
End Class
End Namespace
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