// Shows how to write data into a section of an OPC UA file, using the file provider model.
using System;
using System.IO;
using System.Text;
using OpcLabs.BaseLib.Extensions.FileProviders;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.FileTransfer;
namespace UADocExamples.FileProviders._WritableFileInfo
{
class Write
{
public static void Main1()
{
// Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe)
UAEndpointDescriptor endpointDescriptor = "opc.tcp://localhost:48030";
// A node that represents an instance of OPC UA FileType object.
UANodeDescriptor fileNodeDescriptor = "nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile";
// Instantiate the file transfer client object
var fileTransferClient = new EasyUAFileTransferClient();
Console.WriteLine("Getting writable file info...");
IWritableFileInfo writableFileInfo = fileTransferClient.GetWritableFileInfo(endpointDescriptor, fileNodeDescriptor);
// From this point onwards, the code is independent of the concrete realization of the file provider, and would
// be identical e.g. for files in the physical file system, if the corresponding file provider was used.
// Open the file, write a section of it, and close it.
try
{
Console.WriteLine("Opening file...");
using (Stream stream = writableFileInfo.CreateWriteStream(FileMode.Open, FileAccess.ReadWrite))
{
Console.WriteLine("Writing file section...");
byte[] data = Encoding.UTF8.GetBytes("TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing a section of a file. <<<");
stream.Write(data, 0, data.Length);
Console.WriteLine("Closing file...");
// Disposing of the stream closes the file.
}
}
// Methods in the file provider model throw IOException and other exceptions, but not UAException.
catch (Exception exception)
{
Console.WriteLine($"*** Failure: {exception.GetBaseException().Message}");
return;
}
Console.WriteLine();
Console.WriteLine("Finished...");
}
}
}
# Shows how to write data into a section of an OPC UA file, using the file provider model.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
# Import .NET namespaces.
from System import *
from System.IO import *
from System.Text import *
from OpcLabs.BaseLib.Extensions.FileProviders import *
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.FileTransfer import *
from OpcLabs.EasyOpc.UA.Navigation import *
# Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe).
endpointDescriptor = UAEndpointDescriptor('opc.tcp://localhost:48030')
# A node that represents an OPC UA file system (a root directory).
fileNodeDescriptor = UANodeDescriptor('nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile')
# Instantiate the file transfer client object.
fileTransferClient = EasyUAFileTransferClient()
print('Getting writable file info...')
writableFileInfo = IEasyUAFileTransferExtension.GetWritableFileInfo(fileTransferClient,
endpointDescriptor,
UANamedNodeDescriptor(fileNodeDescriptor))
# From this point onwards, the code is independent of the concrete realization of the file provider, and would
# be identical e.g. for files in the physical file system, if the corresponding file provider was used.
# Open the file, write a section of it, and close it.
stream = None
try:
print('Opening file...')
stream = writableFileInfo.CreateWriteStream(FileMode.Open, FileAccess.ReadWrite)
print('Writing file section...')
data = Encoding.UTF8.GetBytes('TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing a section of a file. '
'<<<')
stream.Write(data, 0, data.Length)
print('Closing file...')
# Disposing of the stream (in the 'finally' block) closes the file.
# Methods in the file provider model throw IOException and other exceptions, but not UAException.
except Exception as exception:
print('*** Failure: ' + exception.GetBaseException().Message)
exit()
finally:
stream and stream.Dispose()
print()
print('Finished.')
' Shows how to write data into a section of an OPC UA file, using the file provider model.
Imports System.IO
Imports System.Text
Imports OpcLabs.BaseLib.Extensions.FileProviders
Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.FileTransfer
Namespace FileProviders._WritableFileInfo
Friend Class Write
Public Shared Sub Main1()
' Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe)
Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://localhost:48030"
' A node that represents an instance of OPC UA FileType object.
Dim fileNodeDescriptor As UANodeDescriptor =
"nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile"
' Instantiate the file transfer client object
Dim fileTransferClient = New EasyUAFileTransferClient
Console.WriteLine("Getting writable file info...")
Dim writableFileInfo As IWritableFileInfo =
fileTransferClient.GetWritableFileInfo(endpointDescriptor, fileNodeDescriptor)
' From this point onwards, the code is independent of the concrete realization of the file provider, and would
' be identical e.g. for files in the physical file system, if the corresponding file provider was used.
' Open the file, write a section of it, and close it.
Try
Console.WriteLine("Opening file...")
Using stream As Stream = writableFileInfo.CreateWriteStream(FileMode.Open, FileAccess.ReadWrite)
Console.WriteLine("Writing file section...")
Dim data As Byte() = Encoding.UTF8.GetBytes("TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing a section of a file. <<<")
stream.Write(data, 0, data.Length)
Console.WriteLine("Closing file...")
' Disposing of the stream closes the file.
End Using
' Methods in the file provider model throw IOException and other exceptions, but not UAException.
Catch exception As Exception
Console.WriteLine("*** Failure: {0}", exception.GetBaseException.Message)
Exit Sub
End Try
Console.WriteLine()
Console.WriteLine("Finished...")
End Sub
End Class
End Namespace
