Examples - OPC Data Access - Browse for servers

Example 1

.NET

C#
Python (.NET)

// This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

using System;
using OpcLabs.EasyOpc;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples.DataAccess._EasyDAClient
{
    class BrowseServers
    {
        public static void Main1()
        {
            // Instantiate the client object.
            var client = new EasyDAClient();
            ServerElementCollection serverElements;
            try
            {
                serverElements = client.BrowseServers("");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            foreach (ServerElement serverElement in serverElements)
                Console.WriteLine($"ServerElements(\"{serverElement.ClsidString}\").ProgId: {serverElement.ProgId}");
        }


        // Example output:
        //
        //ServerElements("c8a12f17-1e03-401e-b53d-6c654dd576da").ProgId: OPCLabs.KitServer.2
    }
}

# This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

# Import .NET namespaces.
from OpcLabs.EasyOpc.DataAccess import *
from OpcLabs.EasyOpc.OperationModel import *


# Instantiate the client object
client = EasyDAClient()

# Perform the operation
try:
    serverElements = IEasyDAClientExtension.BrowseServers(client, '')
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

# Display results
for serverElement in serverElements:
    print('ServerElements("' + serverElement.ClsidString + '"): ' + serverElement.ProgId)

COM

// This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

var Client = new ActiveXObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient");
var ServerElements = Client.BrowseServers("")

for (var objEnum = new Enumerator(ServerElements) ; !objEnum.atEnd() ; objEnum.moveNext()) {
    var ServerElement = objEnum.item();
    WScript.Echo("ServerElements(\"" + ServerElement.UrlString + "\").ProgId: " + ServerElement.ProgId);
}

// This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

$Client = new COM("OpcLabs.EasyOpc.DataAccess.EasyDAClient");

try
{
    $ServerElements = $Client->BrowseServers("");
}
catch (com_exception $e)
{
    printf("*** Failure: %s\n", $e->getMessage());
    Exit();
}

foreach ($ServerElements as $ServerElement)
{
    printf("ServerElements(\"s\").ProgIds\n", $ServerElement->ClsidString, $ServerElement->ProgId);
}

# This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

# The Python for Windows (pywin32) extensions package is needed. Install it using "pip install pypiwin32".
# CAUTION: We now recommend using Python.NET package instead. Full set of examples with Python.NET is available!
import win32com.client
from pywintypes import com_error

# Instantiate the client object
client = win32com.client.Dispatch('OpcLabs.EasyOpc.DataAccess.EasyDAClient') 

# Perform the operation
try:
    serverElements = client.BrowseServers('')
except com_error as e:
    print('*** Failure: ' + e.args[2][1] + ': ' + e.args[2][2])
    exit()

# Display results
for serverElement in serverElements:
    print('ServerElements("' + serverElement.ClsidString + '"): ' + serverElement.ProgId)

Rem This example shows how to obtain all ProgIDs of all OPC Data Access servers on the local machine.

Option Explicit

Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient")
On Error Resume Next
Dim ServerElements: Set ServerElements = Client.BrowseServers("")
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

Dim ServerElement: For Each ServerElement In ServerElements
    WScript.Echo "ServerElements(""" & ServerElement.ClsidString & """).ProgId: " & ServerElement.ProgId
Next

Example 2

.NET

// This example shows all information available about categories that particular OPC servers do support.

using System;
using OpcLabs.EasyOpc;
using OpcLabs.EasyOpc.AlarmsAndEvents;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples._ServerCategories
{
    class General
    {
        public static void Main1()
        {
            // Instantiate the OPC-DA client object.
            var daClient = new EasyDAClient();

            Console.WriteLine();
            Console.WriteLine("OPC DATA ACCESS");
            ServerElementCollection daServerElements;
            try
            {
                daServerElements = daClient.BrowseServers();
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }
            DumpServerElements(daServerElements);

            // Instantiate the OPC-A&E client object.
            var aeClient = new EasyAEClient();

            Console.WriteLine();
            Console.WriteLine("OPC ALARMS AND EVENTS");
            ServerElementCollection aeServerElements;
            try
            {
                aeServerElements = aeClient.BrowseServers();
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }
            DumpServerElements(aeServerElements);
        }

        private static void DumpServerElements(ServerElementCollection serverElements)
        {
            foreach (ServerElement serverElement in serverElements)
            {
                Console.WriteLine($"Categories of \"{serverElement.ProgId}\":");
                ServerCategories serverCategories = serverElement.ServerCategories;
                Console.WriteLine($"    .OpcAlarmsAndEvents10: {serverCategories.OpcAlarmsAndEvents10}");
                Console.WriteLine($"    .OpcDataAccess10: {serverCategories.OpcDataAccess10}");
                Console.WriteLine($"    .OpcDataAccess20: {serverCategories.OpcDataAccess20}");
                Console.WriteLine($"    .OpcDataAccess30: {serverCategories.OpcDataAccess30}");
                Console.WriteLine($"    .ToString(): {serverCategories}");
            }
        }

        
        // Example output:
        //
        //OPC DATA ACCESS
        //Categories of "OPCLabs.KitServer.2":
        //    .OpcAlarmsAndEvents10: False
        //    .OpcDataAccess10: True
        //    .OpcDataAccess20: True
        //    .OpcDataAccess30: True
        //    .ToString(): (OpcDataAccess10, OpcDataAccess20, OpcDataAccess30)
        //
        //OPC ALARMS AND EVENTS
        //Categories of "OPCLabs.KitEventServer.2":
        //    .OpcAlarmsAndEvents10: True
        //    .OpcDataAccess10: False
        //    .OpcDataAccess20: False
        //    .OpcDataAccess30: False
        //    .ToString(): (OpcAlarmsAndEvents10)
    }
}

COM

VBScript

Rem This example shows all information available about categories that particular OPC servers do support.

Option Explicit

Sub DumpServerElements(ByVal ServerElements)
Dim ServerElement: For Each ServerElement In ServerElements
    WScript.Echo "Categories of """ & ServerElement.ProgID & """:"
    With ServerElement.ServerCategories
        WScript.Echo Space(4) & ".OpcAlarmsAndEvents10: " & .OpcAlarmsAndEvents10
        WScript.Echo Space(4) & ".OpcDataAccess10: " & .OpcDataAccess10
        WScript.Echo Space(4) & ".OpcDataAccess20: " & .OpcDataAccess20
        WScript.Echo Space(4) & ".OpcDataAccess30: " & .OpcDataAccess30
        WScript.Echo Space(4) & ".ToString(): " & .ToString()
    End With
Next
End Sub



Dim DAClient: Set DAClient = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient")
WScript.Echo
WScript.Echo "OPC DATA ACCESS"
On Error Resume Next
Dim DAServerElements: Set DAServerElements = DAClient.BrowseServers("")
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0
DumpServerElements DAServerElements

Dim AEClient: Set AEClient = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.EasyAEClient")
WScript.Echo
WScript.Echo "OPC ALARMS AND EVENTS"
On Error Resume Next
Dim AEServerElements: Set AEServerElements = AEClient.BrowseServers("")
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0
DumpServerElements AEServerElements

Example 3

.NET

// This example shows all information available about OPC servers.

using System;
using OpcLabs.EasyOpc;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples._ServerElement
{
    class General
    {
        public static void Main1()
        {
            // Instantiate the client object.
            var client = new EasyDAClient();

            ServerElementCollection serverElements;
            try
            {
                serverElements = client.BrowseServers();
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            foreach (ServerElement serverElement in serverElements)
            {
                Console.WriteLine($"Information about server \"{serverElement}\":");
                Console.WriteLine($"    .ServerClass: {serverElement.ServerClass}");
                Console.WriteLine($"    .ClsidString: {serverElement.ClsidString}");
                Console.WriteLine($"    .ProgId: {serverElement.ProgId}");
                Console.WriteLine($"    .Description: {serverElement.Description}");
                Console.WriteLine($"    .Vendor: {serverElement.Vendor}");
                Console.WriteLine($"    .ServerCategories: {serverElement.ServerCategories}");
                Console.WriteLine($"    .VersionIndependentProgId: {serverElement.VersionIndependentProgId}");
            }


            // Example output:
            //
            //Information about server "opcda:OPCLabs.KitServer.2%7Bc8a12f17-1e03-401e-b53d-6c654dd576da%7D":
            //    .ServerClass: OPCLabs.KitServer.2
            //    .ClsidString: c8a12f17-1e03-401e-b53d-6c654dd576da
            //    .ProgId: OPCLabs.KitServer.2
            //    .Description: OPC Labs Kit Server
            //    .Vendor: OPC Labs, http://www.opclabs.com
            //    .ServerCategories: (OpcDataAccess10, OpcDataAccess20, OpcDataAccess30)
            //    .VersionIndependentProgId: OPCLabs.KitServer
        }
    }
}

COM

VBScript

Rem This example shows all information available about OPC servers.

Option Explicit

Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient")
On Error Resume Next
Dim ServerElements: Set ServerElements = Client.BrowseServers("")
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

Dim ServerElement: For Each ServerElement In ServerElements
    WScript.Echo "Information about server """ & ServerElement & """:"
    With ServerElement
        WScript.Echo Space(4) & ".ServerClass: " & .ServerClass
        WScript.Echo Space(4) & ".ClsidString: " & .ClsidString
        WScript.Echo Space(4) & ".ProgId: " & .ProgId
        WScript.Echo Space(4) & ".Description: " & .Description
        WScript.Echo Space(4) & ".Vendor: " & .Vendor
        WScript.Echo Space(4) & ".ServerCategories.ToString(): " & .ServerCategories.ToString()
        WScript.Echo Space(4) & ".VersionIndependentProgId: " & .VersionIndependentProgId
    End With
Next

Example 1

.NET

COM

Example 2

.NET

COM

Example 3

.NET

COM

Conceptual

Examples - OPC Alarms&Events

Examples - OPC Unified Architecture