OPC Studio User's Guide and Reference
UAApplicationDiscoveryQuery Class
Members 



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.Discovery Namespace : UAApplicationDiscoveryQuery Class
Specifies an OPC UA application discovery query.
Syntax
'Declaration
 
<CLSCompliantAttribute(True)>
<ComDefaultInterfaceAttribute(OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery)>
<ComVisibleAttribute(False)>
<GuidAttribute("F72F44FE-A85C-401F-AEE3-8B6A85B3125A")>
<TypeConverterAttribute(System.ComponentModel.ExpandableObjectConverter)>
<ValueControlAttribute("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.80.82.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", 
   DefaultReadWrite=False, 
   Export=True, 
   PageId=10001)>
<SerializableAttribute()>
Public MustInherit Class UAApplicationDiscoveryQuery 
   Inherits UADiscoveryQuery
   Implements LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable 
'Usage
 
Dim instance As UAApplicationDiscoveryQuery
[CLSCompliant(true)]
[ComDefaultInterface(OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery)]
[ComVisible(false)]
[Guid("F72F44FE-A85C-401F-AEE3-8B6A85B3125A")]
[TypeConverter(System.ComponentModel.ExpandableObjectConverter)]
[ValueControl("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.80.82.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", 
   DefaultReadWrite=false, 
   Export=true, 
   PageId=10001)]
[Serializable()]
public abstract class UAApplicationDiscoveryQuery : UADiscoveryQuery, LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable  
[CLSCompliant(true)]
[ComDefaultInterface(OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery)]
[ComVisible(false)]
[Guid("F72F44FE-A85C-401F-AEE3-8B6A85B3125A")]
[TypeConverter(System.ComponentModel.ExpandableObjectConverter)]
[ValueControl("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.80.82.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", 
   DefaultReadWrite=false, 
   Export=true, 
   PageId=10001)]
[Serializable()]
public ref class UAApplicationDiscoveryQuery abstract : public UADiscoveryQuery, LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.EasyOpc.UA.Discovery.ComTypes._UAApplicationDiscoveryQuery, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable  
Remarks

See also in Knowledge Base: Technical note-OPC UA Discovery in QuickOPC.

 

The various kinds of OPC UA discovery can be generalized into just one method, Discover. This method is given a discovery query argument (of UADiscoveryQuery type) that tells it the requirements for the discovery. The specific kinds of OPC UA discovery described earlier are, in fact, implemented by constructing the discovery query appropriately, and then calling the Discover method.

The UADiscoveryQuery type is an abstract class which is at the root of a structured class hierarchy, with several concrete subclasses:

This generalized discovery mechanism allows for flexibility both on the component and developer sides, and possible future expansion with other kinds of discovery, without a need to introduce new methods into the IEasyUAClient interface.

 

Inheritance Hierarchy

System.Object
   OpcLabs.BaseLib.Object2
      OpcLabs.BaseLib.Info
         OpcLabs.EasyOpc.UA.Discovery.UADiscoveryQuery
            OpcLabs.EasyOpc.UA.Discovery.UAApplicationDiscoveryQuery
               OpcLabs.EasyOpc.UA.Discovery.UAGlobalApplicationDiscoveryQuery
               OpcLabs.EasyOpc.UA.Discovery.UALdsDiscoveryQuery

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also