# OpcDataType Enum

<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>

Specifies the data type of a value. [GetNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getnodeid-opc-uafx-opcdatatype) provides the identifier of the data type and [GetDataType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getdatatype-opc-uafx-opcnodeid) the member for an identifier.

## Syntax

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

```csharp
public enum OpcDataType
```

</div>

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

```vbnet
Public Enum OpcDataType
```

</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) → **OpcDataType**

## Fields

| Name | Value | Description |
|---|---|---|
| <a id="boolean"></a>`Boolean` | `1` | The Boolean data type. |
| <a id="byte"></a>`Byte` | `3` | The Byte data type. |
| <a id="bytestring"></a>`ByteString` | `15` | The ByteString data type. |
| <a id="datetime"></a>`DateTime` | `13` | The DateTime data type. |
| <a id="diagnosticinfo"></a>`DiagnosticInfo` | `25` | The DiagnosticInfo data type. |
| <a id="double"></a>`Double` | `11` | The Double data type. |
| <a id="enumeration"></a>`Enumeration` | `29` | The Enumeration data type. |
| <a id="expandednodeid"></a>`ExpandedNodeId` | `18` | The ExpandedNodeId data type. |
| <a id="extensionobject"></a>`ExtensionObject` | `22` | The ExtensionObject built-in type of OPC UA. [GetNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getnodeid-opc-uafx-opcdatatype) returns [Null](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/members#null) for it. |
| <a id="float"></a>`Float` | `10` | The Float data type. |
| <a id="guid"></a>`Guid` | `14` | The Guid data type. |
| <a id="int16"></a>`Int16` | `4` | The Int16 data type. |
| <a id="int32"></a>`Int32` | `6` | The Int32 data type. |
| <a id="int64"></a>`Int64` | `8` | The Int64 data type. |
| <a id="integer"></a>`Integer` | `27` | The Integer data type. |
| <a id="localizedtext"></a>`LocalizedText` | `21` | The LocalizedText data type. |
| <a id="nodeid"></a>`NodeId` | `17` | The NodeId data type. |
| <a id="null"></a>`Null` | `0` | No data type. [GetDataType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getdatatype-opc-uafx-opcnodeid) returns it for an identifier which is a null reference or empty, and [GetNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getnodeid-opc-uafx-opcdatatype) returns [Null](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/members#null) for it. |
| <a id="number"></a>`Number` | `26` | The Number data type. |
| <a id="object"></a>`Object`<span class="api-meta">since v2.7</span> | `2147483647` | A data type which none of the other members specifies. [GetDataType](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getdatatype-opc-uafx-opcnodeid) returns it for an identifier which is not a null reference and not the identifier of the data type of another member, and [GetNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getnodeid-opc-uafx-opcdatatype) returns [Null](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/members#null) for it. |
| <a id="qualifiedname"></a>`QualifiedName` | `20` | The QualifiedName data type. |
| <a id="sbyte"></a>`SByte` | `2` | The SByte data type. |
| <a id="status"></a>`Status` | `19` | The StatusCode data type. |
| <a id="string"></a>`String` | `12` | The String data type. |
| <a id="uint16"></a>`UInt16` | `5` | The UInt16 data type. |
| <a id="uint32"></a>`UInt32` | `7` | The UInt32 data type. |
| <a id="uint64"></a>`UInt64` | `9` | The UInt64 data type. |
| <a id="uinteger"></a>`UInteger` | `28` | The UInteger data type. |
| <a id="value"></a>`Value` | `23` | The DataValue data type. |
| <a id="variant"></a>`Variant` | `24` | The Variant built-in type of OPC UA. [GetNodeId](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdatatypes/members#getnodeid-opc-uafx-opcdatatype) returns [Null](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnodeid/members#null) for it. |
| <a id="xmlelement"></a>`XmlElement` | `16` | The XmlElement data type. |

## Applies to

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