WriteAllText(IEasyUAFileTransfer,UAEndpointDescriptor,UANamedNodeDescriptor,String,Boolean) Method

Writes text to an OPC UA file.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Sub WriteAllText( _
   ByVal fileTransfer As IEasyUAFileTransfer, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal fileNamedNodeDescriptor As UANamedNodeDescriptor, _
   ByVal text As String, _
   ByVal append As Boolean _
)

'Usage
 
Dim fileTransfer As IEasyUAFileTransfer
Dim endpointDescriptor As UAEndpointDescriptor
Dim fileNamedNodeDescriptor As UANamedNodeDescriptor
Dim text As String
Dim append As Boolean
 
IEasyUAFileTransferExtension2.WriteAllText(fileTransfer, endpointDescriptor, fileNamedNodeDescriptor, text, append)

[Extension()]
public static void WriteAllText( 
   IEasyUAFileTransfer fileTransfer,
   UAEndpointDescriptor endpointDescriptor,
   UANamedNodeDescriptor fileNamedNodeDescriptor,
   string text,
   bool append
)

[Extension()]
public:
static void WriteAllText( 
   IEasyUAFileTransfer^ fileTransfer,
   UAEndpointDescriptor^ endpointDescriptor,
   UANamedNodeDescriptor^ fileNamedNodeDescriptor,
   String^ text,
   bool append
)

Parameters

fileTransfer: The OPC UA file transfer object that will perform the operation.
endpointDescriptor: Endpoint descriptor. Identifies the OPC-UA server.
fileNamedNodeDescriptor: The named node descriptor of the file to which the text should be written.
text: Text to be written to file.
append: True to append to the file contents; False to overwrite the file contents. Default is False.

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.
System.IO.IOException	An I/O error has occurred. 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.

System.IO.IOException

An I/O error has occurred.

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

If the OPC UA file does not already exist, the method creates it.

This method is similar to FileSystem.WriteAllText Method for normal (operating system) files.

CAUTION: This method does not throw the usual OpcLabs.EasyOpc.UA.OperationModel.UAException. Instead, an System.IO.IOException is thrown in case of an error during the operation.

For this method to succeed if it is creating a new file, the fileNamedNodeDescriptor must contain both the named node path (of the parent directory) in the OpcLabs.EasyOpc.UA.Navigation.UANamedNodeDescriptor.NamedNodePath property, and the node name (name of the file) in the OpcLabs.EasyOpc.UA.Navigation.UANamedNodeDescriptor.NodeName property. If this method is opening an existing stream, the file can also be specified using just the final node descriptor (node of the file object) in the OpcLabs.EasyOpc.UA.Navigation.UANamedNodeDescriptor.FinalNodeDescriptor property.

The overloads of this method that do not specify the encoding use UTF-8 encoding to write to the file. To specify a different encoding, use aan appropriate overload of this method.

See OPC UA File Transfer internals for information about Stream buffering.

Recommendation: Whenever possible, do not use this method directly, and use a higher-level abstraction instead. You can obtain a writable file provider (using GetWritableFileProvider), and make use of its methods, and methods available on the writable directory contents (obtained using OpcLabs.BaseLib.Extensions.FileProviders.IWritableDirectory.GetWritableDirectoryContents) or writable file info (obtained using OpcLabs.BaseLib.Extensions.FileProviders.IWritableDirectory.GetWritableFileInfo).

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

IEasyUAFileTransferExtension2 Class
IEasyUAFileTransferExtension2 Members
Overload List
WriteAllText(IWritableFileInfo,String) Method

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