Dns.GetHostByName(String) Metode

Definisi

Ruang nama:

System.Net

Rakitan:

System.Net.NameResolution.dll

Sumber:

Dns.cs

Perhatian

GetHostByName has been deprecated. Use GetHostEntry instead.

Mendapatkan informasi DNS untuk nama host DNS yang ditentukan.

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

Parameter

hostName

String

Nama DNS host.

Mengembalikan

IPHostEntry

Objek IPHostEntry yang berisi informasi host untuk alamat yang ditentukan dalam hostName.

Atribut

ObsoleteAttribute

Pengecualian

ArgumentNullException

hostNameadalah null.

ArgumentOutOfRangeException

Panjangnya hostName lebih besar dari 255 karakter.

SocketException

Terjadi kesalahan saat menyelesaikan hostName.

Contoh

Contoh berikut menggunakan GetHostByName metode untuk mendapatkan informasi DNS untuk nama host DNS yang ditentukan.

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

Keterangan

Metode ini GetHostByName meminta server DNS Internet untuk informasi host. Jika Anda meneruskan string kosong sebagai nama host, metode ini mengambil nama host standar untuk komputer lokal.

Untuk akses asinkron ke informasi DNS, gunakan BeginGetHostByName metode dan EndGetHostByName .

Ipv6Element.Enabled Jika properti diatur ke true, Aliases properti instans yang IPHostEntry dikembalikan tidak diisi oleh metode ini dan akan selalu kosong.

Catatan

Anggota ini memancarkan informasi pelacakan saat Anda mengaktifkan pelacakan jaringan di aplikasi Anda. Untuk informasi selengkapnya, lihat Pelacakan Jaringan di .NET Framework.