Write(IEasyUAClient,UAEndpointDescriptor,UANodeDescriptor,UAAttributeData,Type) Method

Writes into an attribute in an OPC server. Value, status code and timestamps are written. Writes data into a Value attribute of a node, using an endpoint descriptor, node Id, and an attribute type.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function Write( _
   ByVal client As IEasyUAClient, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal nodeDescriptor As UANodeDescriptor, _
   ByVal attributeData As UAAttributeData, _
   ByVal valueType As Type _
) As ValueTuple(Of Boolean,Boolean)

'Usage
 
Dim client As IEasyUAClient
Dim endpointDescriptor As UAEndpointDescriptor
Dim nodeDescriptor As UANodeDescriptor
Dim attributeData As UAAttributeData
Dim valueType As Type
Dim value As ValueTuple(Of Boolean,Boolean)
 
value = IEasyUAClientExtension.Write(client, endpointDescriptor, nodeDescriptor, attributeData, valueType)

[Extension()]
public static ValueTuple<bool,bool> Write( 
   IEasyUAClient client,
   UAEndpointDescriptor endpointDescriptor,
   UANodeDescriptor nodeDescriptor,
   UAAttributeData attributeData,
   Type valueType
)

[Extension()]
public:
static ValueTuple<bool,bool> Write( 
   IEasyUAClient^ client,
   UAEndpointDescriptor^ endpointDescriptor,
   UANodeDescriptor^ nodeDescriptor,
   UAAttributeData^ attributeData,
   Type^ valueType
)

Parameters

client: The client object that will perform the operation.
endpointDescriptor: Endpoint descriptor. Identifies the OPC-UA server.
nodeDescriptor: Node descriptor. Identifies the node in OPC server's address space.
attributeData: Value of an attribute, together with status code and timestamps, to be written.
valueType: Specifies the type that should be used when writing the value.

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.UA.OperationModel.UAException	The OPC UA 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.UA.OperationModel.UAException

The OPC UA 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.

Remarks

The method will attempt to convert the value to the type specified by valueType before writing. This may be needed because the OPC server will only accept values of proper type.

The component will determine the type of the Value attribute from the DataType and ValueRank attributes of the node first. This can have negative implication on the performance, and introduces a dependency of the value written on the behavior of the OPC server itself. Use a method overload that allows to specify the attribute type or type code to prevent this.

You can obtain e.g. by calling one of the browsing methods on EasyUAClientCore object.

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

IEasyUAClientExtension Class
IEasyUAClientExtension Members
Overload List

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