BrowseNodes Method (_EasyAEClient)

Browses the specified area (or root) in OPC server's process area space, and returns information about child nodes (areas or sources) found. Uses server descriptor for specifying the OPC server. A parent area descriptor is passed in. No vendor-specific filtering.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ElementsNotNullAttribute()>
<NotNullAttribute()>
Function BrowseNodes( _
   ByVal serverDescriptor As Object, _
   ByVal parentNodeDescriptor As Object, _
   ByVal browseParameters As Object _
) As AENodeElementCollection

'Usage
 
Dim instance As _EasyAEClient
Dim serverDescriptor As Object
Dim parentNodeDescriptor As Object
Dim browseParameters As Object
Dim value As AENodeElementCollection
 
value = instance.BrowseNodes(serverDescriptor, parentNodeDescriptor, browseParameters)

[ElementsNotNull()]
[NotNull()]
AENodeElementCollection BrowseNodes( 
   object serverDescriptor,
   object parentNodeDescriptor,
   object browseParameters
)

[ElementsNotNull()]
[NotNull()]
AENodeElementCollection^ BrowseNodes( 
   Object^ serverDescriptor,
   Object^ parentNodeDescriptor,
   Object^ browseParameters
)

Parameters

serverDescriptor: The OPC server involved in the operation.
parentNodeDescriptor: Descriptor for the parent area to be browsed (can be the root).
browseParameters: Contains filtering conditions.

Return Value

The method returns a keyed collection of OpcLabs.EasyOpc.AlarmsAndEvents.AddressSpace.AENodeElement values, each containing information about a particular node (area or source) found. The keys of the keyed collection are the names of the nodes.

Exceptions

Exception Description

Exception	Description
System.ArgumentNullException	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.
OpcLabs.EasyOpc.OperationModel.OpcException	The OPC "Classic" (or OPC XML-DA) 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.

System.ArgumentNullException

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.

OpcLabs.EasyOpc.OperationModel.OpcException

The OPC "Classic" (or OPC XML-DA) 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.

Requirements

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

Reference

_EasyAEClient Interface
_EasyAEClient Members

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