# OpcTimestampSource Enum

> Reference: Defines the source of the timestamp to use for OpcValue instances.

<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>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Defines the source of the timestamp to use for [OpcValue](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/) instances.

## Syntax

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

```csharp
public enum OpcTimestampSource
```

</div>

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

```vbnet
Public Enum OpcTimestampSource
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → [ValueType](https://learn.microsoft.com/dotnet/api/system.valuetype) → [Enum](https://learn.microsoft.com/dotnet/api/system.enum) → **OpcTimestampSource**

## Fields

| Name | Value | Description |
|---|---|---|
| <a id="maxvalue"></a>`MaxValue` | `4` | The [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/members#sourcetimestamp) will be changed to [MaxValue](https://learn.microsoft.com/dotnet/api/system.datetime.maxvalue) even if the user specified a different timestamp. |
| <a id="minvalue"></a>`MinValue` | `1` | The [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/members#sourcetimestamp) will be changed to [MinValue](https://learn.microsoft.com/dotnet/api/system.datetime.minvalue) even if the user specified a different timestamp. |
| <a id="now"></a>`Now` | `3` | The [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/members#sourcetimestamp) will be changed to [Now](https://learn.microsoft.com/dotnet/api/system.datetime.now) even if the user specified a different timestamp. |
| <a id="utcnow"></a>`UtcNow` | `2` | The [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/members#sourcetimestamp) will be changed to [UtcNow](https://learn.microsoft.com/dotnet/api/system.datetime.utcnow) even if the user specified a different timestamp. |
| <a id="value"></a>`Value` | `0` | The [SourceTimestamp](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcvalue/members#sourcetimestamp) will be kept unchanged. This means that the user defined timestamp remains unchanged. In case there is no user defined timestamp, the default timestamp will be used. |

## Applies to

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