Public Sub DisplayHostAddress(IpAddressString As [String])
    Try
        Dim hostIPAddress As IPAddress = IPAddress.Parse(IpAddressString)
        
        ' Call the GetHostByAddress(IPAddress) method, passing an IPAddress object as an argument 
        ' to obtain an IPHostEntry instance, containing address information for the specified host.
        
        Dim hostInfo As IPHostEntry = Dns.GetHostByAddress(hostIPAddress)
        ' Get the IP address list that resolves to the host names contained in 
        ' the Alias property.
        Dim address As IPAddress() = hostInfo.AddressList
        ' Get the alias names of the above addresses in the IP address list.
        Dim [alias] As [String]() = hostInfo.Aliases
        
        Console.WriteLine(("Host name : " + hostInfo.HostName))
        Console.WriteLine(ControlChars.Cr + "Aliases :")
        Dim index As Integer
        For index = 0 To [alias].Length - 1
            Console.WriteLine([alias](index))
        Next index
        Console.WriteLine(ControlChars.Cr + "IP address list : ")

        For index = 0 To address.Length - 1
            Console.WriteLine(address(index))
        Next index
        
    Catch e As SocketException
        Console.WriteLine("SocketException caught!!!")
        Console.WriteLine(("Source : " + e.Source))
        Console.WriteLine(("Message : " + e.Message))
        
    Catch e As FormatException
        Console.WriteLine("FormatException caught!!!")
        Console.WriteLine(("Source : " + e.Source))
        Console.WriteLine(("Message : " + e.Message))
        
    Catch e As ArgumentNullException
        Console.WriteLine("ArgumentNullException caught!!!")
        Console.WriteLine(("Source : " + e.Source))
        Console.WriteLine(("Message : " + e.Message))
        
    Catch e As Exception
        Console.WriteLine("Exception caught!!!")
        Console.WriteLine(("Source : " + e.Source))
        Console.WriteLine(("Message : " + e.Message))
    End Try
End Sub

' 导入命名空间
Imports System.Net
Imports System.Net.Sockets


Public Class Tester
    Public Shared Sub Main

        Dim strHostName As String

        Try
            strHostName = Dns.GetHostByAddress("68.129.2.123").HostName
            Console.WriteLine(strHostName)
        Catch exfe As FormatException
            Console.WriteLine(exfe.Message)
        Catch exse As SocketException
            Console.WriteLine(exse.Message)
        End Try
    End Sub
End Class