UADataMappingOperations Enumeration

Possible mapping operations on OPC Unified Architecture (OPC-UA) data.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ComVisibleAttribute(False)>
<DisplayName2Attribute("OPC-UA Data Mapping Operations")>
<FlagsAttribute()>
Public Enum UADataMappingOperations 
   Inherits System.Enum
   Implements System.IComparable, System.IConvertible, System.IFormattable

'Usage
 
Dim instance As UADataMappingOperations

[ComVisible(false)]
[DisplayName2("OPC-UA Data Mapping Operations")]
[Flags()]
public enum UADataMappingOperations : System.Enum, System.IComparable, System.IConvertible, System.IFormattable

[ComVisible(false)]
[DisplayName2("OPC-UA Data Mapping Operations")]
[Flags()]
public enum class UADataMappingOperations : public System.Enum, System.IComparable, System.IConvertible, System.IFormattable

Members

Member	Value	Description
All	7	All operations (Read, Write, Subscribe).
None	0	No operation.
Read	1	A Read operation.
ReadAndSubscribe	5	Read and Subscribe operations.
ReadAndWrite	3	Read and Write operations.
Subscribe	4	A Subscribe operation.
Write	2	A Write operation.
WriteAndSubscribe	6	Write and Subscribe operations.

Remarks

There are several things you can do with OPC Data: you can read from them, write to them, or subscribe to their changes. Not all mappings should be involved in all operations, and you therefore need to specify the operations that are of interest to you.

For DAClientItemMapping (OPC Data Access items), doing this means properly setting the Operations argument of the DAItem attribute. You can set it to one of the following values, or their combination:

DAItemMappingOperations.Read: A Read operation.
DAItemMappingOperations.Write: A Write operation.
DAItemMappingOperations.Subscribe: A Subscribe operation.

If you want a combination, you can use a logical OR of the individual values, or use a predefined symbolic name such as ReadAndWrite, ReadAndSubscribe, etc. By default, the Operations argument is set to DAItemMappingOperations.All, meaning that the mapping will be involved in all operations.

There is just one mapping operation for DAClientPropertyMapping (OPC Data Access properties) – the “Get” operation that obtains the value of the OPC property. For OPC-DA property mappings, it is therefore neither necessary nor possible to specify the operation(s) that certain mapping should be involved in.

For UAClientDataMapping (in OPC-UA), you specify the operations by properly setting the Operations argument of the UAData attribute. You can set it to one of the following values, or their combination:

UADataMappingOperations.Read: A Read operation.
UADataMappingOperations.Write: A Write operation.
UADataMappingOperations.Subscribe: A Subscribe operation.

The operations do not get actually executed until you write and run a code that does it. See Invoking the Operations for details.

Inheritance Hierarchy

System.Object
   System.ValueType
      System.Enum
         OpcLabs.EasyOpc.UA.LiveMapping.UADataMappingOperations

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

OpcLabs.EasyOpc.UA.LiveMapping Namespace

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