Begins to asynchronously lookup the IP address(es) for a host.
Namespace:
JHSoftwareAssembly: JHSoftware.DnsClient (in JHSoftware.DnsClient.dll) Version: 1.0.1.0 (1.0.1.0)
Syntax
| C# |
|---|
public static IAsyncResult BeginLookupHost( string hostName, DnsClient..::.IPVersion ipVersion, DnsClient..::.RequestOptions options, AsyncCallback callback, Object state ) |
| Visual Basic (Declaration) |
|---|
Public Shared Function BeginLookupHost ( _ hostName As String, _ ipVersion As DnsClient..::.IPVersion, _ options As DnsClient..::.RequestOptions, _ callback As AsyncCallback, _ state As Object _ ) As IAsyncResult |
Parameters
- hostName
- Type: System..::.String
The host name to look up. IDNs may be either in native or encoded form (xn--...).
- ipVersion
- Type: JHSoftware..::.DnsClient..::.IPVersion
The IP version (IPv4 / IPv6) of the IP addresses to return.
- options
- Type: JHSoftware..::.DnsClient..::.RequestOptions
The options to use with the DNS request. Specify null/Nothing for default options.
- callback
- Type: System..::.AsyncCallback
The AsyncCallback delegate.
- state
- Type: System..::.Object
An object that contains state information for this request.
Return Value
An IAsyncResult that references the asynchronous operation.
Exceptions
| Exception | Condition |
|---|---|
| System..::.ArgumentException | Invalid host name or IP version. |
| JHSoftware..::.DnsClient..::.NoDnsServersException | No DNS servers where specified, and no DNS servers could be found in this computer's IP configuration |