TryParseRelative Method (_UABrowsePathParser)

Attempts to parse a string containing a relative browse path.

Syntax

[CanBeNull()]
StringParsingError TryParseRelative( 
   string value,
   object browsePathElementCollection
)

[CanBeNull()]
StringParsingError^ TryParseRelative( 
   String^ value,
   Object^ browsePathElementCollection
)

'Declaration
 
<CanBeNullAttribute()>
Function TryParseRelative( _
   ByVal value As String, _
   ByVal browsePathElementCollection As Object _
) As StringParsingError

'Usage
 
Dim instance As _UABrowsePathParser
Dim value As String
Dim browsePathElementCollection As Object
Dim value As StringParsingError
 
value = instance.TryParseRelative(value, browsePathElementCollection)

Parameters

value: The string containing the relative browse path to be parsed.
browsePathElementCollection: OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElementCollection. If successful, an original collection of browse path elements, expanded by elements corresponding to the input string.

Return Value

Returns null if successful; otherwise, some OpcLabs.BaseLib.IStringParsingError indicating the reason of the failure.

Example

.NET

COM

// Attempts to parse a relative OPC-UA browse path and displays its elements.

using System;
using OpcLabs.BaseLib;
using OpcLabs.EasyOpc.UA.Navigation;
using OpcLabs.EasyOpc.UA.Navigation.Parsing;

namespace UADocExamples._UABrowsePathParser
{
    class TryParseRelative
    {
        public static void Main1()
        {
            var browsePathElements = new UABrowsePathElementCollection();

            var browsePathParser = new UABrowsePathParser();
            IStringParsingError stringParsingError = browsePathParser.TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", browsePathElements);

            // Display results
            if (!(stringParsingError is null))
            {
                Console.WriteLine("*** Error: {0}", stringParsingError);
                return;
            }

            foreach (UABrowsePathElement browsePathElement in browsePathElements)
                Console.WriteLine(browsePathElement);

            // Example output:
            // /Data
            // .Dynamic
            // .Scalar
            // .CycleComplete        
        }
    }
}

# Attempts to parse a relative OPC-UA browse path and displays its elements.

# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.Navigation import *
from OpcLabs.EasyOpc.UA.Navigation.Parsing import *


browsePathElements = UABrowsePathElementCollection()

browsePathParser = UABrowsePathParser()
stringParsingError = browsePathParser.TryParseRelative('/Data.Dynamic.Scalar.CycleComplete', browsePathElements)

# Display results.
if stringParsingError is not None:
    print('*** Error: ', stringParsingError, sep='')
    exit()

for browsePathElement in browsePathElements:
    print(browsePathElement)

print()
print('Finished.')

' Attempts to parse a relative OPC-UA browse path and displays its elements.

Imports System
Imports OpcLabs.BaseLib
Imports OpcLabs.EasyOpc.UA.Navigation
Imports OpcLabs.EasyOpc.UA.Navigation.Parsing

Namespace _UABrowsePathParser
    Friend Class TryParseRelative
        Public Shared Sub Main1()
            Dim browsePathElements = New UABrowsePathElementCollection()

            Dim browsePathParser = New UABrowsePathParser()
            Dim stringParsingError As IStringParsingError = browsePathParser.TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", browsePathElements)

            ' Display results
            If Not stringParsingError Is Nothing Then
                Console.WriteLine("*** Error: {0}", stringParsingError)
                Exit Sub
            End If

            For Each browsePathElement As UABrowsePathElement In browsePathElements
                Console.WriteLine(browsePathElement)
            Next browsePathElement

            ' Example output:
            ' /Data
            ' .Dynamic
            ' .Scalar
            ' .CycleComplete
        End Sub
    End Class
End Namespace

// Attempts to parse a relative OPC-UA browse path and displays its elements.

class procedure TryParseRelative.Main;
var
  BrowsePathElement: _UABrowsePathElement;
  BrowsePathElements: _UABrowsePathElementCollection;
  BrowsePathParser: OpcLabs_EasyOpcUA_TLB._UABrowsePathParser;
  Count: Cardinal;
  Element: OleVariant;
  ElementEnumerator: IEnumVariant;
  StringParsingError: _StringParsingError;
begin
  BrowsePathElements := CoUABrowsePathElementCollection.Create;

  BrowsePathParser := CoUABrowsePathParser.Create;
  StringParsingError := BrowsePathParser.TryParseRelative('/Data.Dynamic.Scalar.CycleComplete', BrowsePathElements);

  // Display results
  if StringParsingError <> nil then
  begin
    WriteLn('*** Error: ', StringParsingError.ToString);
    Exit;
  end;

  ElementEnumerator := BrowsePathElements.GetEnumerator;
  while (ElementEnumerator.Next(1, Element, Count) = S_OK) do
  begin
    BrowsePathElement := IUnknown(Element) as _UABrowsePathElement;
    WriteLn(BrowsePathElement.ToString);
  end;

  // Example output:
  // /Data
  // .Dynamic
  // .Scalar
  // .CycleComplete

end;

// Attempts to parse a relative OPC-UA browse path and displays its elements.

$BrowsePathElements = new COM("OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElementCollection");

$BrowsePathParser = new COM("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser");

$StringParsingError = $BrowsePathParser->TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", $BrowsePathElements);

// Display results
if (!is_null($StringParsingError)) {
    printf("*** Error: %s\n", $StringParsingError);
    exit();
}

printf("StartingNodeId: %s\n", $BrowsePath->StartingNodeId);

printf("Elements:\n");

for ($i = 0; $i < $BrowsePathElements->Count; $i++)
{
    printf("%s\n", $BrowsePathElements[$i]);
}

// Example output:
// /Data
// .Dynamic
// .Scalar
// .CycleComplete

Rem Attempts to parse a relative OPC-UA browse path and displays its elements.

Private Sub TryParseRelative_Main_Command_Click()
    OutputText = ""
    
    Dim BrowsePathElements As New UABrowsePathElementCollection
    
    Dim BrowsePathParser As New UABrowsePathParser

    Dim stringParsingError As stringParsingError
    Set stringParsingError = BrowsePathParser.TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", BrowsePathElements)
    
    ' Display results
    If Not stringParsingError Is Nothing Then
        OutputText = OutputText & "*** Error: " & stringParsingError & vbCrLf
        Exit Sub
    End If
    
    Dim BrowsePathElement: For Each BrowsePathElement In BrowsePathElements
        OutputText = OutputText & BrowsePathElement & vbCrLf
    Next

    ' Example output:
    '/Data
    '.Dynamic
    '.Scalar
    '.CycleComplete
End Sub

Visual Basic (VB 6.0)
VBScript

Rem Attempts to parse a relative OPC-UA browse path and displays its elements.

Private Sub TryParseRelative_Main_Command_Click()
    OutputText = ""
    
    Dim BrowsePathElements As New UABrowsePathElementCollection
    
    Dim BrowsePathParser As New UABrowsePathParser

    Dim stringParsingError As stringParsingError
    Set stringParsingError = BrowsePathParser.TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", BrowsePathElements)
    
    ' Display results
    If Not stringParsingError Is Nothing Then
        OutputText = OutputText & "*** Error: " & stringParsingError & vbCrLf
        Exit Sub
    End If
    
    Dim BrowsePathElement: For Each BrowsePathElement In BrowsePathElements
        OutputText = OutputText & BrowsePathElement & vbCrLf
    Next

    ' Example output:
    '/Data
    '.Dynamic
    '.Scalar
    '.CycleComplete
End Sub

Rem Attempts to parse a relative OPC-UA browse path and displays its elements.

Option Explicit

Dim BrowsePathElements: Set BrowsePathElements = CreateObject("OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElementCollection")

Dim BrowsePathParser: Set BrowsePathParser = CreateObject("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser")
Dim StringParsingError: Set StringParsingError = BrowsePathParser.TryParseRelative("/Data.Dynamic.Scalar.CycleComplete", BrowsePathElements)

' Display results
If Not (StringParsingError Is Nothing) Then
    WScript.Echo "*** Error: " & StringParsingError
    WScript.Quit
End If

Dim BrowsePathElement: For Each BrowsePathElement In BrowsePathElements
    WScript.Echo BrowsePathElement
Next

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

_UABrowsePathParser Interface
_UABrowsePathParser Members

Send Documentation Feedback. Resources: Knowledge Base. Technical support: Online Forums, FAQ.