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Dns.GetHostByName(String) Metodo

Definizione

Attenzione

GetHostByName is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202

Attenzione

GetHostByName has been deprecated. Use GetHostEntry instead.

Attenzione

GetHostByName is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202

Ottiene le informazioni DNS per il nome host DNS specificato.

public:
 static System::Net::IPHostEntry ^ GetHostByName(System::String ^ hostName);
[System.Obsolete("GetHostByName is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202")]
public static System.Net.IPHostEntry GetHostByName (string hostName);
[System.Obsolete("GetHostByName has been deprecated. Use GetHostEntry instead.")]
public static System.Net.IPHostEntry GetHostByName (string hostName);
[System.Obsolete("GetHostByName is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202")]
public static System.Net.IPHostEntry GetHostByName (string hostName);
public static System.Net.IPHostEntry GetHostByName (string hostName);
[<System.Obsolete("GetHostByName is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202")>]
static member GetHostByName : string -> System.Net.IPHostEntry
[<System.Obsolete("GetHostByName has been deprecated. Use GetHostEntry instead.")>]
static member GetHostByName : string -> System.Net.IPHostEntry
[<System.Obsolete("GetHostByName is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202")>]
static member GetHostByName : string -> System.Net.IPHostEntry
static member GetHostByName : string -> System.Net.IPHostEntry
Public Shared Function GetHostByName (hostName As String) As IPHostEntry

Parametri

hostName
String

Nome DNS dell'host.

Restituisce

Oggetto IPHostEntry contenente informazioni sull'host per l'indirizzo specificato nel parametro hostName.

Attributi

Eccezioni

hostName è null.

La lunghezza del parametro hostName è maggiore di 255 caratteri.

Si è verificato un errore durante la risoluzione del parametro hostName.

Esempio

Nell'esempio seguente viene usato il GetHostByName metodo per ottenere le informazioni DNS per il nome host DNS specificato.

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

Commenti

Il GetHostByName metodo esegue una query sul server DNS Internet per ottenere informazioni sull'host. Se si passa una stringa vuota come nome host, questo metodo recupera il nome host standard per il computer locale.

Per l'accesso asincrono alle informazioni DNS, usare i BeginGetHostByName metodi e EndGetHostByName .

Se la Ipv6Element.Enabled proprietà è impostata su true, la Aliases proprietà dell'istanza IPHostEntry restituita non viene popolata da questo metodo e sarà sempre vuota.

Nota

Questo membro genera informazioni di traccia quando si abilita la traccia di rete nell'applicazione. Per altre informazioni, vedere Traccia di rete in .NET Framework.

Si applica a