OPC Studio User's Guide and Reference
GetEffectiveHostNames Method (AbstractEasyUAClientServerApplication)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.Application Namespace > AbstractEasyUAClientServerApplication Class : GetEffectiveHostNames Method
A collection of alternate host names to be used, or null to use the HostNames specified for the application.

The value of this parameter can be null (Nothing in Visual Basic).

The individual elements of the parameter value cannot be null (Nothing in Visual Basic).

Get the effective application host names.
Syntax
'Declaration
 
Public MustOverride Function GetEffectiveHostNames( _
   ByVal alternateHostNames As StringCollection _
) As StringCollection
'Usage
 
Dim instance As AbstractEasyUAClientServerApplication
Dim alternateHostNames As StringCollection
Dim value As StringCollection
 
value = instance.GetEffectiveHostNames(alternateHostNames)
public abstract StringCollection GetEffectiveHostNames( 
   StringCollection alternateHostNames
)
public:
abstract StringCollection^ GetEffectiveHostNames( 
   StringCollection^ alternateHostNames
) 

Parameters

alternateHostNames
A collection of alternate host names to be used, or null to use the HostNames specified for the application.

The value of this parameter can be null (Nothing in Visual Basic).

The individual elements of the parameter value cannot be null (Nothing in Visual Basic).

Return Value

If alternate host names are empty, returns default host names. Otherwise, returns the alternate host names.

This method never returns null (Nothing in Visual Basic).

The individual elements of the returned value are never null (Nothing in Visual Basic).

Exceptions
ExceptionDescription

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

The OPC UA operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Remarks

This method is pure, i.e. it does not have observable side effects.

For server applications, the default host names consist of known DNS and NetBIOS names and IPv4 and IPv6 addresses of the local host. For applications that are not servers, the default host names are empty.

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also