Dns.GetHostByName(String) Método

Definición

Espacio de nombres:

System.Net

Ensamblado:

System.Net.NameResolution.dll

Source:

Dns.cs

Precaución

GetHostByName has been deprecated. Use GetHostEntry instead.

Obtiene la información de DNS para el nombre de host DNS especificado.

public:
 static System::Net::IPHostEntry ^ GetHostByName(System::String ^ hostName);

[System.Obsolete("GetHostByName has been deprecated. Use GetHostEntry instead.")]
public static System.Net.IPHostEntry GetHostByName (string hostName);

[<System.Obsolete("GetHostByName has been deprecated. Use GetHostEntry instead.")>]
static member GetHostByName : string -> System.Net.IPHostEntry

Public Shared Function GetHostByName (hostName As String) As IPHostEntry

Parámetros

hostName

String

Nombre DNS del host.

Devoluciones

IPHostEntry

Objeto IPHostEntry que contiene información de host para la dirección especificada en hostName.

Atributos

ObsoleteAttribute

Excepciones

ArgumentNullException

hostName es null.

ArgumentOutOfRangeException

La longitud de hostName es mayor que 255 caracteres.

SocketException

Se detectó un error al resolver hostName.

Ejemplos

En el ejemplo siguiente se usa el GetHostByName método para obtener la información dns del nombre de host DNS especificado.

try
{
   IPHostEntry^ hostInfo = Dns::GetHostByName( hostName );
   
   // Get the IP address list that resolves to the host names contained in the
   // Alias property.
   array<IPAddress^>^address = hostInfo->AddressList;
   
   // Get the alias names of the addresses in the IP address list.
   array<String^>^alias = hostInfo->Aliases;
   Console::WriteLine( "Host name : {0}", 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 : {0}", e->Source );
   Console::WriteLine( "Message : {0}", e->Message );
}
catch ( ArgumentNullException^ e ) 
{
   Console::WriteLine( "ArgumentNullException caught!!!" );
   Console::WriteLine( "Source : {0}", e->Source );
   Console::WriteLine( "Message : {0}", e->Message );
}
catch ( Exception^ e ) 
{
   Console::WriteLine( "Exception caught!!!" );
   Console::WriteLine( "Source : {0}", e->Source );
   Console::WriteLine( "Message : {0}", e->Message );
}

 try
 {
    IPHostEntry hostInfo = Dns.GetHostByName(hostName);
    // 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(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);
 }

Public Sub DisplayHostName(hostName As [String])
    Try
        ' Call the GetHostByName method, passing a DNS style host name(for example,
        ' "www.contoso.com") as an argument to obtain an IPHostEntry instance, that 
        ' contains information for the specified host.
        
        Dim hostInfo As IPHostEntry = Dns.GetHostByName(hostName)
        ' 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 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 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

Comentarios

El GetHostByName método consulta el servidor DNS de Internet para obtener información de host. Si pasa una cadena vacía como nombre de host, este método recupera el nombre de host estándar para el equipo local.

Para obtener acceso asincrónico a la información de DNS, use los BeginGetHostByName métodos y EndGetHostByName .

Si la Ipv6Element.Enabled propiedad se establece trueen , la Aliases propiedad de la IPHostEntry instancia devuelta no se rellena mediante este método y siempre estará vacía.

Nota

Este miembro emite información de seguimiento al habilitar el seguimiento de red en la aplicación. Para obtener más información, vea Seguimiento de red en .NET Framework.