// This example shows how to react to events in order to initiate and finalize data collection in the push data provision
// model.
// You can use any OPC UA client, including our Connectivity Explorer and OpcCmd utility, to connect to the server.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client, server and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-OPCStudio-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.
using System;
using System.Timers;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.NodeSpace;
namespace UAServerDocExamples._UAServerNode
{
class Starting_Stopped
{
public static void Main1()
{
// Instantiate the server object.
// By default, the server will run on endpoint URL "opc.tcp://localhost:48040/".
var server = new EasyUAServer();
// Create a read-only data variable.
var dataVariable = UADataVariable.CreateIn(server.Objects, "ReadThisVariable")
.ValueType<int>()
.Writable(false);
dataVariable.Starting += (sender, args) =>
{
// Create a timer for pushing the data for OPC reads.
var timer = new Timer
{
Interval = 1000,
AutoReset = true,
};
// Set the read attribute data of the data variable to a random value whenever the timer interval elapses.
// Note that this example shows the basic concept, however there is also an UpdateReadAttributeData method that
// can be used in most cases to achieve slightly more concise code.
var random = new Random();
timer.Elapsed += (s, a) =>
dataVariable.ReadAttributeData = new UAAttributeData(random.Next(), DateTime.UtcNow);
timer.Start();
// Associate the timer with the data variable.
dataVariable.State = timer;
};
dataVariable.Stopped += (sender, args) =>
{
// Obtain the timer associated with the data variable.
var timer = (Timer)((UADataVariable)sender).State;
// Stop the timer.
timer.Stop();
};
// Start the server.
Console.WriteLine("The server is starting...");
server.Start();
Console.WriteLine("The server is started.");
Console.WriteLine();
// Let the user decide when to stop.
Console.WriteLine("Press Enter to stop the server...");
Console.ReadLine();
// Stop the server.
Console.WriteLine("The server is stopping...");
server.Stop();
Console.WriteLine("The server is stopped.");
}
}
}
' This example shows how to react to events in order to initiate and finalize data collection in the push data provision
' model.
' You can use any OPC UA client, including our Connectivity Explorer and OpcCmd utility, to connect to the server.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
' a commercial license in order to use Online Forums, and we reply to every post.
Imports System
Imports System.Timers
Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.NodeSpace
Namespace _UAServerNode
Partial Friend Class Starting_Stopped
Shared Sub Main1()
' Instantiate the server object.
' By default, the server will run on endpoint URL "opc.tcp://localhost:48040/".
Dim server = New EasyUAServer()
' Create a read-only data variable.
Dim dataVariable = UADataVariable.CreateIn(server.Objects, "ReadThisVariable") _
.ValueType(Of Integer)() _
.Writable(False)
AddHandler dataVariable.Starting, Sub(sender, args)
' Create a timer for pushing the data for OPC reads.
Dim timer = New Timer With
{
.Interval = 1000,
.AutoReset = True
}
' Set the read attribute data of the data variable to a random value whenever the timer interval elapses.
' Note that this example shows the basic concept, however there is also an UpdateReadAttributeData method that
' can be used in most cases to achieve slightly more concise code.
Dim random = New Random()
AddHandler timer.Elapsed, Sub(s, a)
dataVariable.ReadAttributeData = New UAAttributeData(random.Next(), DateTime.UtcNow)
End Sub
timer.Start()
' Associate the timer with the data variable.
dataVariable.State = timer
End Sub
AddHandler dataVariable.Stopped, Sub(sender, args)
' Obtain the timer associated with the data variable.
Dim timer = CType(CType(sender, UADataVariable).State, Timer)
' Stop the timer.
timer.Stop()
End Sub
' Start the server.
Console.WriteLine("The server is starting...")
server.Start()
Console.WriteLine("The server is started.")
Console.WriteLine()
' Let the user decide when to stop.
Console.WriteLine("Press Enter to stop the server...")
Console.ReadLine()
' Stop the server.
Console.WriteLine("The server is stopping...")
server.Stop()
Console.WriteLine("The server is stopped.")
End Sub
End Class
End Namespace
