# OpcDataTypeMemberOffsetAttribute Class

<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">OpcDataTypeMemberOffsetAttribute Members</a></dd>
<dt>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Declares a field or property of a custom data type, to that the member belongs on that this attribute is applied, with an absolute zero-based start-offset within the stream of its custom data type. Using the [Offset](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypememberoffsetattribute/members#offset) specified means, that the members data starts at the byte specified by [Offset](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypememberoffsetattribute/members#offset). All preceding bytes are skipped; if not read for a prior member. When writing a member with a specific [Offset](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypememberoffsetattribute/members#offset) all preceding bytes are written using zeros; if not written using a prior member. If this attribute is not defined, the first member is read and written using zero as its offset.

## Syntax

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

```csharp
public class OpcDataTypeMemberOffsetAttribute : Attribute
```

</div>

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

```vbnet
<AttributeUsage(AttributeTargets.Property Or AttributeTargets.Field, AllowMultiple:=False, Inherited:=False)>
Public Class OpcDataTypeMemberOffsetAttribute
    Inherits Attribute
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → [Attribute](https://learn.microsoft.com/dotnet/api/system.attribute) → **OpcDataTypeMemberOffsetAttribute**

## Constructors

| Name | Description |
|---|---|
| [OpcDataTypeMemberOffsetAttribute](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypememberoffsetattribute/members#opcdatatypememberoffsetattribute) | Initializes a new instance of the OpcDataTypeMemberOffsetAttribute class using the `offset` value specified. |

## Properties

| Name | Description |
|---|---|
| [Offset](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypememberoffsetattribute/members#offset) | Gets the position of the first byte which introduces the data of the member. |

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

## Applies to

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