Dns.Resolve(String) Method
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Caution
Resolve has been deprecated. Use GetHostEntry instead.
Caution
Resolve is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202
Caution
Resolve is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202
Resolves a DNS host name or IP address to an IPHostEntry instance.
public:
static System::Net::IPHostEntry ^ Resolve(System::String ^ hostName);[System.Obsolete("Resolve has been deprecated. Use GetHostEntry instead.")]
public static System.Net.IPHostEntry Resolve(string hostName);[System.Obsolete("Resolve is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202")]
public static System.Net.IPHostEntry Resolve(string hostName);[System.Obsolete("Resolve is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202")]
public static System.Net.IPHostEntry Resolve(string hostName);public static System.Net.IPHostEntry Resolve(string hostName);[<System.Obsolete("Resolve has been deprecated. Use GetHostEntry instead.")>]
static member Resolve : string -> System.Net.IPHostEntry[<System.Obsolete("Resolve is obsoleted for this type, please use GetHostEntry instead. https://go.microsoft.com/fwlink/?linkid=14202")>]
static member Resolve : string -> System.Net.IPHostEntry[<System.Obsolete("Resolve is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202")>]
static member Resolve : string -> System.Net.IPHostEntrystatic member Resolve : string -> System.Net.IPHostEntryPublic Shared Function Resolve (hostName As String) As IPHostEntry- hostName
- String
A DNS-style host name or IP address.
An IPHostEntry instance that contains address information about the host specified in hostName.
- Attributes
hostName is null.
The length of hostName is greater than 255 characters.
An error is encountered when resolving hostName.
The following example uses the Resolve method to resolve an IP address to an IPHostEntry instance.
try
{
IPHostEntry^ hostInfo = Dns::Resolve( hostString );
// 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 ( NullReferenceException^ e )
{
Console::WriteLine( "NullReferenceException 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.Resolve(hostString);
// 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(NullReferenceException e)
{
Console.WriteLine("NullReferenceException 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);
}
Try
' Call the Resolve method passing a DNS style host name or an IP address in
' dotted-quad notation (for example, "www.contoso.com" or "207.46.131.199") to
' obtain an IPHostEntry instance that contains address information for the
' specified host.
Dim hostInfo As IPHostEntry = Dns.Resolve(hostString)
' 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 NullReferenceException
Console.WriteLine("NullReferenceException 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
The Resolve method queries a DNS server for the IP address associated with a host name or IP address.
When hostName is a DNS-style host name associated with multiple IP addresses, only the first IP address that resolves to that host name is returned.
If the Ipv6Element.Enabled property is set to true, the Aliases property of the IPHostEntry instance returned is not populated by this method and will always be empty.
Note
This member emits trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.
| Product | Versions (Obsolete) |
|---|---|
| .NET | (Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10) |
| .NET Framework | 1.1 (2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1) |
| .NET Standard | (2.0, 2.1) |
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