FindFile(IEasyUAFileTransfer,UAEndpointDescriptor,UANodeDescriptor,IReadOnlyList<String>,String) Method

Finds a file object under the specified parent directory.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function FindFile( _
   ByVal fileTransfer As IEasyUAFileTransfer, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal directoryNodeDescriptor As UANodeDescriptor, _
   ByVal directoryPathElements As IReadOnlyList(Of String), _
   ByVal fileName As String _
) As ValueTuple(Of UANodeDescriptor,UANodeDescriptor)

'Usage
 
Dim fileTransfer As IEasyUAFileTransfer
Dim endpointDescriptor As UAEndpointDescriptor
Dim directoryNodeDescriptor As UANodeDescriptor
Dim directoryPathElements As IReadOnlyList(Of String)
Dim fileName As String
Dim value As ValueTuple(Of UANodeDescriptor,UANodeDescriptor)
 
value = IEasyUAFileTransferExtension.FindFile(fileTransfer, endpointDescriptor, directoryNodeDescriptor, directoryPathElements, fileName)

[Extension()]
public static ValueTuple<UANodeDescriptor,UANodeDescriptor> FindFile( 
   IEasyUAFileTransfer fileTransfer,
   UAEndpointDescriptor endpointDescriptor,
   UANodeDescriptor directoryNodeDescriptor,
   IReadOnlyList<string> directoryPathElements,
   string fileName
)

[Extension()]
public:
static ValueTuple<UANodeDescriptor^,UANodeDescriptor^> FindFile( 
   IEasyUAFileTransfer^ fileTransfer,
   UAEndpointDescriptor^ endpointDescriptor,
   UANodeDescriptor^ directoryNodeDescriptor,
   IReadOnlyList<String^>^ directoryPathElements,
   String^ fileName
)

Parameters

fileTransfer: The OPC UA file transfer object that will perform the operation.
endpointDescriptor: Endpoint descriptor. Identifies the OPC-UA server.
directoryNodeDescriptor: Node descriptor of the OPC UA directory.
directoryPathElements: A path consisting of names of subdirectories starting from directoryNodeDescriptor forwards.
fileName: The name of the file to find.

Return Value

Returns a tuple consisting of a node descriptor of the parent directory, and a node descriptor of the file object. The node descriptor of the file object is non-null, if the file was found; it is null otherwise.

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.UA.OperationModel.UAException	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.

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.UA.OperationModel.UAException

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.

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

IEasyUAFileTransferExtension Class
IEasyUAFileTransferExtension Members
Overload List
FindDirectory(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodePath) Method
FindFileOrDirectory(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor) Method
GetFile(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor) Method
FindFile Method
IsFile(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor) Method

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