DeleteFileIfExists(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor) Method

Deletes an OPC UA file if it exists (does nothing if the file does not exist).

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function DeleteFileIfExists( _
   ByVal fileTransfer As IEasyUAFileTransfer, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal namedNodeDescriptor As UANamedNodeDescriptor _
) As Boolean

'Usage
 
Dim fileTransfer As IEasyUAFileTransfer
Dim endpointDescriptor As UAEndpointDescriptor
Dim namedNodeDescriptor As UANamedNodeDescriptor
Dim value As Boolean
 
value = IEasyUAFileTransferExtension.DeleteFileIfExists(fileTransfer, endpointDescriptor, namedNodeDescriptor)

[Extension()]
public static bool DeleteFileIfExists( 
   IEasyUAFileTransfer fileTransfer,
   UAEndpointDescriptor endpointDescriptor,
   UANamedNodeDescriptor namedNodeDescriptor
)

[Extension()]
public:
static bool DeleteFileIfExists( 
   IEasyUAFileTransfer^ fileTransfer,
   UAEndpointDescriptor^ endpointDescriptor,
   UANamedNodeDescriptor^ namedNodeDescriptor
)

Parameters

fileTransfer: The OPC UA file transfer object that will perform the operation.
endpointDescriptor: Endpoint descriptor. Identifies the OPC-UA server.
namedNodeDescriptor: A named node description of the OPC UA file to delete.

Return Value

Returns true if the file existed and has been deleted; returns false if the file does not exist.

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.

Remarks

For this method to succeed, the namedNodeDescriptor must contain the named node path and the node name.

Recommendation: Whenever possible, do not use this method directly, and use a higher-level abstraction instead. See e.g. the GetWritableFileInfo(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor) method, which allows you to obtain an object that can be used to manage files, in a way that is generic and not tied to OPC UA specifics.

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
Delete Method

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