# OpcClassicInterfaces Members

> Reference: Provides the interface specifications of OPC Classic supported by the SDK.

<dl class="api-definition">
<dt>Type</dt>
<dd><a href="./">OpcClassicInterfaces</a></dd>
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx.classic">Opc.UaFx.Classic</a></dd>
<dt>Assembly</dt>
<dd>Opc.UaFx.Advanced.dll</dd>
<dt>Package</dt>
<dd>Opc.UaFx.Advanced v2.59.0</dd>
</dl>

## Fields

### Ae10

<span class="api-meta">static</span>

Represents the interface specification OPC Alarms and Events 1.0.

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

```csharp
public static readonly OpcClassicInterface Ae10
```

</div>

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

```vbnet
Public Shared ReadOnly Ae10 As OpcClassicInterface
```

</div>

**Field value**

[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)

### Da10

<span class="api-meta">static</span>

Represents the interface specification OPC Data Access 1.0.

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

```csharp
public static readonly OpcClassicInterface Da10
```

</div>

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

```vbnet
Public Shared ReadOnly Da10 As OpcClassicInterface
```

</div>

**Field value**

[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)

### Da20

<span class="api-meta">static</span>

Represents the interface specification OPC Data Access 2.0.

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

```csharp
public static readonly OpcClassicInterface Da20
```

</div>

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

```vbnet
Public Shared ReadOnly Da20 As OpcClassicInterface
```

</div>

**Field value**

[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)

### Da30

<span class="api-meta">static</span>

Represents the interface specification OPC Data Access 3.0.

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

```csharp
public static readonly OpcClassicInterface Da30
```

</div>

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

```vbnet
Public Shared ReadOnly Da30 As OpcClassicInterface
```

</div>

**Field value**

[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)

### Hda10

<span class="api-meta">static</span>

Represents the interface specification OPC Historical Data Access 1.0.

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

```csharp
public static readonly OpcClassicInterface Hda10
```

</div>

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

```vbnet
Public Shared ReadOnly Hda10 As OpcClassicInterface
```

</div>

**Field value**

[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)

## Methods

### All

<span class="api-meta">static</span>

Retrieves all interface specifications of OPC Classic supported by the SDK.

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

```csharp
public static IEnumerable<OpcClassicInterface> All()
```

</div>

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

```vbnet
Public Shared Function All() As IEnumerable(Of OpcClassicInterface)
```

</div>

**Returns**

[IEnumerable](https://learn.microsoft.com/dotnet/api/system.collections.generic.ienumerable-1)&lt;[OpcClassicInterface](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterface/)&gt;

A sequence of [Ae10](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterfaces/members#ae10), [Da10](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterfaces/members#da10), [Da20](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterfaces/members#da20), [Da30](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterfaces/members#da30) and [Hda10](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.classic.opcclassicinterfaces/members#hda10).