# IOpcDataFieldInfo Interface

<span class="api-meta">since v2.8</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>Members</dt>
<dd><a href="./members">IOpcDataFieldInfo Members</a></dd>
<dt>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Defines the metadata of a field declared by a data type.

## Syntax

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

```csharp
public interface IOpcDataFieldInfo
```

</div>

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

```vbnet
Public Interface IOpcDataFieldInfo
```

</div>

## Derived types

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

## Properties

| Name | Description |
|---|---|
| [DeclaringType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#declaringtype) | Gets the type that declares the current IOpcDataFieldInfo. |
| [FieldType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#fieldtype) | Gets the type of value this field provides. |
| [IsOptional](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#isoptional) | Gets a value indicating whether the current field might not necessarily exist in the object defined by the [DeclaringType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#declaringtype). |
| [Length](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#length) | Gets the length of the field expressed either explicit or implicit using a different IOpcDataFieldInfo. |
| [Name](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#name) | Gets the name of the current IOpcDataFieldInfo. |
| [ReflectedType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#reflectedtype) | Gets the type that was used to obtain this instance of IOpcDataFieldInfo. |
| [Switch](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#switch) | Gets the switch condition which applies to the current IOpcDataFieldInfo. |

## Methods

| Name | Description |
|---|---|
| [GetValue](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#getvalue) | Gets the value of the field supported by the given object `instance`. |
| [SetValue](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.iopcdatafieldinfo/members#setvalue) | Sets the value of the field supported by the given object `instance`. |

## Applies to

| Package | Versions |
|---|---|
| Opc.UaFx.Advanced | v2.8–v2.59 |