GetPropertyValue<TValue>(IEasyDAClient,ServerDescriptor,DANodeDescriptor,DAPropertyDescriptor) Method

Gets a value of typed OPC property, using descriptor objects for the OPC server, node, and the property.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function GetPropertyValue(Of TValue)( _
   ByVal client As IEasyDAClient, _
   ByVal serverDescriptor As ServerDescriptor, _
   ByVal nodeDescriptor As DANodeDescriptor, _
   ByVal propertyDescriptor As DAPropertyDescriptor _
) As TValue

'Usage
 
Dim client As IEasyDAClient
Dim serverDescriptor As ServerDescriptor
Dim nodeDescriptor As DANodeDescriptor
Dim propertyDescriptor As DAPropertyDescriptor
Dim value As TValue
 
value = IEasyDAClientExtension2.GetPropertyValue(Of TValue)(client, serverDescriptor, nodeDescriptor, propertyDescriptor)

[Extension()]
[NotNull()]
public static TValue GetPropertyValue<TValue>( 
   IEasyDAClient client,
   ServerDescriptor serverDescriptor,
   DANodeDescriptor nodeDescriptor,
   DAPropertyDescriptor propertyDescriptor
)

[Extension()]
[NotNull()]
public:
static TValue^ GetPropertyValuegeneric<typename TValue>
( 
   IEasyDAClient^ client,
   ServerDescriptor^ serverDescriptor,
   DANodeDescriptor^ nodeDescriptor,
   DAPropertyDescriptor^ propertyDescriptor
)

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.
propertyDescriptor: The descriptor of the OPC property involved in the operation.

Type Parameters

TValue: The type of property value.

Return Value

If successful, the function returns the actual value of the OPC property requested.

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.
OpcLabs.EasyOpc.OperationModel.OpcException	The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause. 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.

OpcLabs.EasyOpc.OperationModel.OpcException

The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

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.

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

IEasyDAClientExtension2 Class
IEasyDAClientExtension2 Members
Overload List

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