# OpcNodeAccessEventArgs Class

> Reference: Provides the event data for the events BeforeRead, AfterRead, BeforeWrite and AfterWrite.

<dl class="api-definition">
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx.server">Opc.UaFx.Server</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">OpcNodeAccessEventArgs Members</a></dd>
</dl>

Provides the event data for the events [BeforeRead](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodemanager/members#beforeread), [AfterRead](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodemanager/members#afterread), [BeforeWrite](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodemanager/members#beforewrite) and [AfterWrite](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodemanager/members#afterwrite).

## Syntax

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

```csharp
public class OpcNodeAccessEventArgs : EventArgs
```

</div>

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

```vbnet
Public Class OpcNodeAccessEventArgs
    Inherits EventArgs
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → [EventArgs](https://learn.microsoft.com/dotnet/api/system.eventargs) → **OpcNodeAccessEventArgs**

## Constructors

| Name | Description |
|---|---|
| [OpcNodeAccessEventArgs](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodeaccesseventargs/members#opcnodeaccesseventargs) | Initializes a new instance of the OpcNodeAccessEventArgs class using the `context` and `tokens` specified. |

## Properties

| Name | Description |
|---|---|
| [Context](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodeaccesseventargs/members#context) | Gets the context of the read or write operation. |
| [Tokens](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodeaccesseventargs/members#tokens) | Gets the tokens of the attribute values to read or to write. |

Inherits members from [EventArgs](https://learn.microsoft.com/dotnet/api/system.eventargs).

## Applies to

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