# OpcModelChangeActions Enum

<span class="api-meta">since v2.22</span>

<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>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Defines possible change actions happening to a node.

## Syntax

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

```csharp
public enum OpcModelChangeActions : byte
```

</div>

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

```vbnet
<Flags>
Public Enum OpcModelChangeActions As Byte
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → [ValueType](https://learn.microsoft.com/dotnet/api/system.valuetype) → [Enum](https://learn.microsoft.com/dotnet/api/system.enum) → **OpcModelChangeActions**

## Fields

| Name | Value | Description |
|---|---|---|
| <a id="datatypechanged"></a>`DataTypeChanged` | `16` | Indiciates that the node is a variable or variable type node and its [DataType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcattribute/#datatype) attribute has changed. |
| <a id="nodeadded"></a>`NodeAdded` | `1` | Indicates the node has been added. |
| <a id="nodedeleted"></a>`NodeDeleted` | `2` | Indicates the node has been deleted. |
| <a id="none"></a>`None` | `0` | Indicates no change actions were performed. |
| <a id="referenceadded"></a>`ReferenceAdded` | `4` | Indicates a reference has been added. The node may be either a source node or target node. Note that an added bidirectional reference is reflected by two changes. |
| <a id="referencedeleted"></a>`ReferenceDeleted` | `8` | Indicates a reference has been deleted. The node may be either a source node or target node. Note that a deleted bidirectional reference is reflected by two changes. |

## Applies to

| Package | Versions |
|---|---|
| Opc.UaFx.Advanced | v2.22–v2.59 |