# IOpcReadNodesService Interface

> Reference: Defines a specialized IOpcService<TResponse, TRequest> which can be used to read one or more attributes (see OpcAttribute) of one or more nodes.

<dl class="api-definition">
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx.services">Opc.UaFx.Services</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">IOpcReadNodesService Members</a></dd>
<dt>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Defines a specialized [IOpcService&lt;TResponse, TRequest&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.services.iopcservice-2/) which can be used to read one or more attributes (see [OpcAttribute](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcattribute/)) of one or more nodes.

## Syntax

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

```csharp
public interface IOpcReadNodesService
```

</div>

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

```vbnet
<CLSCompliant(False)>
Public Interface IOpcReadNodesService
```

</div>

## Base interfaces

<ul class="api-implements">
<li><a href="../opc.uafx.services.iopcservice-2/">IOpcService</a>&lt;<a href="../opc.uafx.services.opcreadnodesresponse/">OpcReadNodesResponse</a>, <a href="../opc.uafx.services.opcreadnodesrequest/">OpcReadNodesRequest</a>&gt;</li>
</ul>

## Derived types

- [OpcClient](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.client.opcclient/)

## Properties

| Name | Description |
|---|---|
| [MaxNodesPerRead](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.services.iopcreadnodesservice/members#maxnodesperread)<span class="api-meta">since v2.9</span> | Gets or sets the maximum number of nodes which shall be read using a single read request. |
| [UsedMaxNodesPerRead](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.services.iopcreadnodesservice/members#usedmaxnodesperread)<span class="api-meta">since v2.9</span> | Gets the maximum number of nodes which are read using a single read request. |

## Methods

| Name | Description |
|---|---|
| [ReadNodes](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.services.iopcreadnodesservice/members#readnodes)<span class="api-meta">2 overloads</span> | Reads one or more values of one or more attributes of one or more nodes using the specified `commands`. |

Inherits members from [IOpcService&lt;OpcReadNodesResponse, OpcReadNodesRequest&gt;](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.services.iopcservice-2/members).

## Applies to

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