Dns.GetHostByAddress Method

Gets DNS host information for an IP address.

Overload List

Creates an IPHostEntry instance from the specified IPAddress.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Shared Function GetHostByAddress(IPAddress) As IPHostEntry

[C#] public static IPHostEntry GetHostByAddress(IPAddress);

[C++] public: static IPHostEntry* GetHostByAddress(IPAddress*);

[JScript] public static function GetHostByAddress(IPAddress) : IPHostEntry;

Creates an IPHostEntry instance from an IP address.

Supported by the .NET Compact Framework.

[Visual Basic] Overloads Public Shared Function GetHostByAddress(String) As IPHostEntry

[C#] public static IPHostEntry GetHostByAddress(string);

[C++] public: static IPHostEntry* GetHostByAddress(String*);

[JScript] public static function GetHostByAddress(String) : IPHostEntry;

Example

[Visual Basic, C#, C++] The following example creates a IPHostEntry from an IPAddress.

[Visual Basic, C#, C++] Note   This example shows how to use one of the overloaded versions of GetHostByAddress. For other examples that might be available, see the individual overload topics.

[Visual Basic] 
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 'DisplayHostAddress

[C#] 
try 
{
   IPAddress hostIPAddress = IPAddress.Parse(IpAddressString);
   IPHostEntry hostInfo = Dns.GetHostByAddress(hostIPAddress);
   // Get the IP address list that resolves to the host names contained in 
   // the Alias property.
   IPAddress[] address = hostInfo.AddressList;
   // Get the alias names of the addresses in the IP address list.
   String[] alias = hostInfo.Aliases;

   Console.WriteLine("Host name : " + hostInfo.HostName);
   Console.WriteLine("\nAliases :");
   for(int index=0; index < alias.Length; index++) {
     Console.WriteLine(alias[index]);
   } 
   Console.WriteLine("\nIP address list : ");
   for(int index=0; index < address.Length; index++) {
      Console.WriteLine(address[index]);
   }
}
catch(SocketException e) 
{
     Console.WriteLine("SocketException caught!!!");
   Console.WriteLine("Source : " + e.Source);
   Console.WriteLine("Message : " + e.Message);
}
catch(FormatException e)
{
     Console.WriteLine("FormatException caught!!!");
   Console.WriteLine("Source : " + e.Source);
   Console.WriteLine("Message : " + e.Message);
}
catch(ArgumentNullException e)
{
     Console.WriteLine("ArgumentNullException caught!!!");
   Console.WriteLine("Source : " + e.Source);
   Console.WriteLine("Message : " + e.Message);
}
catch(Exception e)
{
    Console.WriteLine("Exception caught!!!");
    Console.WriteLine("Source : " + e.Source);
    Console.WriteLine("Message : " + e.Message);
}

[C++] 
try {
   IPAddress* hostIPAddress = IPAddress::Parse(IpAddressString);
   IPHostEntry* hostInfo = Dns::GetHostByAddress(hostIPAddress);
   // Get the IP address list that resolves to the host names contained in
   // the Alias property.
   IPAddress* address[] = hostInfo->AddressList;
   // Get the alias names of the addresses in the IP address list.
   String*  alias[] = hostInfo->Aliases;

   Console::WriteLine(S"Host name : {0}", hostInfo->HostName);
   Console::WriteLine(S"\nAliases :");
   for (int index=0; index < alias->Length; index++)
      Console::WriteLine(alias->Item[index]);

   Console::WriteLine(S"\nIP address list : ");
   for (int index=0; index < address->Length; index++)
      Console::WriteLine(address->Item[index]);

} catch (SocketException* e) {
   Console::WriteLine(S"SocketException caught!!!");
   Console::WriteLine(S"Source : {0}", e->Source);
   Console::WriteLine(S"Message : {0}", e->Message);
} catch (FormatException* e) {
   Console::WriteLine(S"FormatException caught!!!");
   Console::WriteLine(S"Source : {0}", e->Source);
   Console::WriteLine(S"Message : {0}", e->Message);
} catch (ArgumentNullException* e) {
   Console::WriteLine(S"ArgumentNullException caught!!!");
   Console::WriteLine(S"Source : {0}", e->Source);
   Console::WriteLine(S"Message : {0}", e->Message);
} catch (Exception* e) {
   Console::WriteLine(S"Exception caught!!!");
   Console::WriteLine(S"Source : {0}", e->Source);
   Console::WriteLine(S"Message : {0}", e->Message);
}

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button in the upper-left corner of the page.

See Also

Dns Class | Dns Members | System.Net Namespace