Dns.GetHostByName(String) Méthode

Définition

Espace de noms:

System.Net

Assembly:

System.Net.NameResolution.dll

Source:

Dns.cs

Attention

GetHostByName has been deprecated. Use GetHostEntry instead.

Obtient les données DNS pour le nom d'hôte DNS spécifié.

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

Paramètres

hostName

String

Nom DNS de l'hôte.

Retours

IPHostEntry

Objet IPHostEntry qui contient les données d'hôte pour l'adresse spécifiée dans hostName.

Attributs

ObsoleteAttribute

Exceptions

ArgumentNullException

hostName a la valeur null.

ArgumentOutOfRangeException

La longueur de hostName est supérieure à 255 caractères.

SocketException

Une erreur s'est produite lors de la résolution de hostName.

Exemples

L’exemple suivant utilise la GetHostByName méthode pour obtenir les informations DNS pour le nom d’hôte DNS spécifié.

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

Remarques

La GetHostByName méthode interroge le serveur DNS Internet pour obtenir des informations sur l’hôte. Si vous passez une chaîne vide comme nom d’hôte, cette méthode récupère le nom d’hôte standard de l’ordinateur local.

Pour un accès asynchrone aux informations DNS, utilisez les BeginGetHostByName méthodes et EndGetHostByName .

Si la propriété a la Ipv6Element.Enabledtruevaleur , la Aliases propriété de l’instance IPHostEntry retournée n’est pas remplie par cette méthode et sera toujours vide.

Notes

Ce membre émet des informations de trace lorsque vous activez le suivi réseau dans votre application. Pour plus d’informations, consultez Suivi réseau dans le .NET Framework.