GetPropertyValueDictionary(IEasyDAClient,ServerDescriptor,DANodeDescriptor,IEnumerable<DAPropertyId>) Method

Obtains a DAPropertyValueDictionary filled with OPC property values for a given OPC item. Obtains a dictionary filled with known OPC property values for a given OPC item. You can specify the property Ids.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
<ElementsNotNullAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function GetPropertyValueDictionary( _
   ByVal client As IEasyDAClient, _
   ByVal serverDescriptor As ServerDescriptor, _
   ByVal nodeDescriptor As DANodeDescriptor, _
   ByVal propertyIds As IEnumerable(Of DAPropertyId) _
) As DAPropertyValueDictionary

'Usage
 
Dim client As IEasyDAClient
Dim serverDescriptor As ServerDescriptor
Dim nodeDescriptor As DANodeDescriptor
Dim propertyIds As IEnumerable(Of DAPropertyId)
Dim value As DAPropertyValueDictionary
 
value = IEasyDAClientExtension2.GetPropertyValueDictionary(client, serverDescriptor, nodeDescriptor, propertyIds)

[Extension()]
[ElementsNotNull()]
[NotNull()]
public static DAPropertyValueDictionary GetPropertyValueDictionary( 
   IEasyDAClient client,
   ServerDescriptor serverDescriptor,
   DANodeDescriptor nodeDescriptor,
   IEnumerable<DAPropertyId> propertyIds
)

[Extension()]
[ElementsNotNull()]
[NotNull()]
public:
static DAPropertyValueDictionary^ GetPropertyValueDictionary( 
   IEasyDAClient^ client,
   ServerDescriptor^ serverDescriptor,
   DANodeDescriptor^ nodeDescriptor,
   IEnumerable<DAPropertyId^>^ propertyIds
)

Parameters

client: The client object that will perform the operation.
serverDescriptor: The OPC server involved in the operation.
nodeDescriptor: The descriptor of the OPC node involved in the operation.
propertyIds: Specifies which OPC properties should be obtained and returned.

Return Value

Returns a dictionary of OpcLabs.BaseLib.OperationModel.ValueResult objects keyed by OpcLabs.EasyOpc.DataAccess.DAPropertyId.

Exceptions

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.

Remarks

This method allows you to obtain a dictionary of property values for a given OPC item, where a key to the dictionary is the property Id. You can pass in a set of property Ids that you are interested in, or have the method obtain all well-known OPC properties. You can then easily extract the value of any property by looking it up in a dictionary (as opposed to having to numerically index into an array, as with the base OpcLabs.EasyOpc.DataAccess.IEasyDAClientExtension.GetMultiplePropertyValues method).

Using implicit conversions, you can pass an item ID in place of node descriptor.

Example

CSharp
VB.NET

// This example shows how to obtain a dictionary of OPC property values for an OPC item, and extract property values.

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

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

            // Get dictionary of property values, for all well-known properties
            DAPropertyValueDictionary propertyValueDictionary;
            try
            {
                propertyValueDictionary = client.GetPropertyValueDictionary("", "OPCLabs.KitServer.2", "Simulation.Random");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            // Display some of the obtained property values
            // The production code should also check for the .Exception first, before getting .Value
            Console.WriteLine("propertyValueDictionary[DAPropertyId.AccessRights].Value: {0}",
                propertyValueDictionary[DAPropertyIds.AccessRights].Value);
            Console.WriteLine("propertyValueDictionary[DAPropertyId.DataType].Value: {0}",
                propertyValueDictionary[DAPropertyIds.DataType].Value);
            Console.WriteLine("propertyValueDictionary[DAPropertyId.Timestamp].Value: {0}",
                propertyValueDictionary[DAPropertyIds.Timestamp].Value);
        }
    }
}

' This example shows how to obtain a dictionary of OPC property values for an OPC item, and extract property values.

Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.DataAccess.Extensions
Imports OpcLabs.EasyOpc.OperationModel

Namespace DocExamples.DataAccess._EasyDAClientExtension
    Friend Class GetPropertyValueDictionary
        Public Shared Sub Main1()
            Dim client = New EasyDAClient()

            ' Get dictionary of property values, for all well-known properties
            Dim propertyValueDictionary As DAPropertyValueDictionary
            Try
                propertyValueDictionary = client.GetPropertyValueDictionary("", "OPCLabs.KitServer.2", "Simulation.Random")
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            ' Display some of the obtained property values
            ' The production code should also check for the .Exception first, before getting .Value
            Console.WriteLine("propertyValueDictionary[DAPropertyId.AccessRights].Value: {0}", propertyValueDictionary(DAPropertyIds.AccessRights).Value)
            Console.WriteLine("propertyValueDictionary[DAPropertyId.DataType].Value: {0}", propertyValueDictionary(DAPropertyIds.DataType).Value)
            Console.WriteLine("propertyValueDictionary[DAPropertyId.Timestamp].Value: {0}", propertyValueDictionary(DAPropertyIds.Timestamp).Value)
        End Sub
    End Class
End Namespace

CSharp
VB.NET

// This example shows how to obtain a dictionary of OPC property values for an OPC item, and extract property values.

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

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

            // Get dictionary of property values, for all well-known properties
            DAPropertyValueDictionary propertyValueDictionary;
            try
            {
                propertyValueDictionary = client.GetPropertyValueDictionary("", "OPCLabs.KitServer.2", "Simulation.Random");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            // Display some of the obtained property values
            // The production code should also check for the .Exception first, before getting .Value
            Console.WriteLine("propertyValueDictionary[DAPropertyId.AccessRights].Value: {0}",
                propertyValueDictionary[DAPropertyIds.AccessRights].Value);
            Console.WriteLine("propertyValueDictionary[DAPropertyId.DataType].Value: {0}",
                propertyValueDictionary[DAPropertyIds.DataType].Value);
            Console.WriteLine("propertyValueDictionary[DAPropertyId.Timestamp].Value: {0}",
                propertyValueDictionary[DAPropertyIds.Timestamp].Value);
        }
    }
}

' This example shows how to obtain a dictionary of OPC property values for an OPC item, and extract property values.

Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.DataAccess.Extensions
Imports OpcLabs.EasyOpc.OperationModel

Namespace DocExamples.DataAccess._EasyDAClientExtension
    Friend Class GetPropertyValueDictionary
        Public Shared Sub Main1()
            Dim client = New EasyDAClient()

            ' Get dictionary of property values, for all well-known properties
            Dim propertyValueDictionary As DAPropertyValueDictionary
            Try
                propertyValueDictionary = client.GetPropertyValueDictionary("", "OPCLabs.KitServer.2", "Simulation.Random")
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            ' Display some of the obtained property values
            ' The production code should also check for the .Exception first, before getting .Value
            Console.WriteLine("propertyValueDictionary[DAPropertyId.AccessRights].Value: {0}", propertyValueDictionary(DAPropertyIds.AccessRights).Value)
            Console.WriteLine("propertyValueDictionary[DAPropertyId.DataType].Value: {0}", propertyValueDictionary(DAPropertyIds.DataType).Value)
            Console.WriteLine("propertyValueDictionary[DAPropertyId.Timestamp].Value: {0}", propertyValueDictionary(DAPropertyIds.Timestamp).Value)
        End Sub
    End Class
End Namespace

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2012, Windows Server 2016; .NET Core, .NET 5, .NET 6: Linux, macOS, Microsoft Windows

Reference

IEasyDAClientExtension2 Class
IEasyDAClientExtension2 Members
Overload List