# OpcConditionVariableNode Class

<dl class="api-definition">
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx">Opc.UaFx</a></dd>
<dt>Assembly</dt>
<dd>Opc.UaFx.Advanced.dll</dd>
<dt>Package</dt>
<dd>Opc.UaFx.Advanced v2.59.0</dd>
<dt>Members</dt>
<dd><a href="./members">OpcConditionVariableNode Members</a></dd>
</dl>

Defines a variable node which is used by various information elements of a condition that are not considered to be states. However, a change in their value is considered important and supposed to trigger an event notification. These information elements are called condition variables.

## Syntax

<div class="api-signature" data-lang="csharp">

```csharp
public class OpcConditionVariableNode : OpcDataVariableNode
```

</div>

<div class="api-signature" data-lang="vbnet">

```vbnet
<OpcNodeType(9002)>
Public Class OpcConditionVariableNode
    Inherits OpcDataVariableNode
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → [OpcNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnode/) → [OpcInstanceNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcinstancenode/) → [OpcVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablenode/) → [OpcDataVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatavariablenode/) → **OpcConditionVariableNode**

## Implements

<ul class="api-implements">
<li><a href="../opc.uafx.iopcnode/">IOpcNode</a></li>
<li><a href="../opc.uafx.iopcnodeinfo/">IOpcNodeInfo</a></li>
<li><a href="../opc.uafx.iopcvariablenodeinfo/">IOpcVariableNodeInfo</a></li>
</ul>

## Derived types

- [OpcConditionVariableNode&lt;T&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode-1/)
- [OpcStatusConditionVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcstatusconditionvariablenode/)
- [OpcTextConditionVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opctextconditionvariablenode/)

## Constructors

| Name | Description |
|---|---|
| [OpcConditionVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode/members#opcconditionvariablenode)<span class="api-meta">10 overloads</span> | Initializes a new instance of the OpcConditionVariableNode class accessible by the `name` specified. |

## Properties

| Name | Description |
|---|---|
| [DefaultTypeDefinitionId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode/members#defaulttypedefinitionid)<span class="api-meta">protected · override</span> | Gets the default identifier which identifies the node that defines the underlying node type from that this [OpcInstanceNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcinstancenode/) has been created. |
| [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode/members#sourcetimestamp) | Gets or sets a value which indicates the time of the last change of the [Value](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablenode/members#value) of this condition variable. |
| [SourceTimestampNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode/members#sourcetimestampnode) | Gets the [OpcPropertyNode&lt;T&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcpropertynode-1/) of the [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionvariablenode/members#sourcetimestamp) property. |

Inherits members from [OpcVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablenode/members), [OpcInstanceNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcinstancenode/members), [OpcNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnode/members).

## Applies to

| Package | Versions |
|---|---|
| Opc.UaFx.Advanced | v2.5–v2.59 |