Mono Documentation

Begins the asynchronous execution of a DNS query to obtain address information about the specified host. [Edit]

[System.Obsolete("Use BeginGetHostEntry instead")]
public static IAsyncResult BeginGetHostByName (string hostName, AsyncCallback requestCallback, object stateObject)

Parameters

hostName
A string containing the DNS name of the host. [Edit]
requestCallback
A AsyncCallback delegate, or null . [Edit]
stateObject
An application-defined object, or null . [Edit]

Returns

A IAsyncResult instance that contains information about the asynchronous operation. [Edit]

Permissions

Type Reason
System.Net.DnsPermission [Edit] Requires unrestricted permission for accessing DNS information. See System.Net.DnsPermission and System.Security.Permissions.PermissionState.Unrestricted.

Type	Reason
System.Net.DnsPermission [Edit]	Requires unrestricted permission for accessing DNS information. See System.Net.DnsPermission and System.Security.Permissions.PermissionState.Unrestricted.

Exceptions

Type Reason
ArgumentNullException hostName is null . [Edit]
System.Net.Sockets.SocketException An error was encountered executing the DNS query . [Edit]
System.Security.SecurityException The caller does not have permission to access DNS information. [Edit]

Type	Reason
ArgumentNullException	hostName is `null` . [Edit]
System.Net.Sockets.SocketException	An error was encountered executing the DNS query . [Edit]
System.Security.SecurityException	The caller does not have permission to access DNS information. [Edit]

Remarks

This method starts an asynchronous request for information about the specified host. To retrieve the results of the query and release resources allocated by this method, call the Dns.EndGetHostByName(IAsyncResult) method and specify the IAsyncResult object returned by this method.
Note: The Dns.EndGetHostByName(IAsyncResult) method should be called exactly once for each call to Dns.BeginGetHostByName(string, AsyncCallback, object) .
If the requestCallback parameter is not null, the method referenced by requestCallback is invoked when the asynchronous operation completes. The IAsyncResult object returned by this method is passed as the argument to the method referenced by requestCallback . The method referenced by requestCallback can retrieve the results of the query by calling Dns.EndGetHostByName(IAsyncResult) .
The stateObject parameter can be any object that the caller wishes to have available for the duration of the asynchronous operation. This object is available via the IAsyncResult.AsyncState property of the object returned by this method. [Edit]

Requirements