# OpcReadNodeIdArrayVariableValueCallback Delegate

<span class="api-meta">since v2.54</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>
</dl>

Represents the method that will read the value of a node identifier array variable node.

## Syntax

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

```csharp
public delegate OpcVariableValue<OpcNodeId[]> OpcReadNodeIdArrayVariableValueCallback(
    OpcReadVariableValueContext<OpcNodeIdArrayVariableNode> context,
    OpcVariableValue<OpcNodeId[]> value)
```

</div>

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

```vbnet
Public Delegate Function OpcReadNodeIdArrayVariableValueCallback(
    context As OpcReadVariableValueContext(Of OpcNodeIdArrayVariableNode),
    value As OpcVariableValue(Of OpcNodeId())) As OpcVariableValue(Of OpcNodeId())
```

</div>

## Parameters

| Name | Type | Description |
|---|---|---|
| `context` | [OpcReadVariableValueContext](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcreadvariablevaluecontext-1/)&lt;[OpcNodeIdArrayVariableNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeidarrayvariablenode/)&gt; | The [OpcReadVariableValueContext&lt;T&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcreadvariablevaluecontext-1/) to use to read the node identifier variable value. |
| `value` | [OpcVariableValue](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablevalue-1/)&lt;[OpcNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/)[]&gt; | The preliminary [OpcVariableValue&lt;T&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablevalue-1/). |

## Returns

[OpcVariableValue](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablevalue-1/)&lt;[OpcNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/)[]&gt;

The determined [OpcVariableValue&lt;T&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvariablevalue-1/).

## Applies to

| Package | Versions |
|---|---|
| Opc.UaFx.Advanced | v2.54–v2.59 |