OPC Studio User's Guide and Reference
Key Property (UAKeyValuePair)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA Namespace > UAKeyValuePair Class : Key Property
The key of the value.
Syntax
'Declaration
 
Public Property Key As UAQualifiedName
'Usage
 
Dim instance As UAKeyValuePair
Dim value As UAQualifiedName
 
instance.Key = value
 
value = instance.Key
public UAQualifiedName Key {get; set;}
public:
property UAQualifiedName^ Key {
   UAQualifiedName^ get();
   void set (    UAQualifiedName^ value);
}

Property Value

The value of this property cannot be null (Nothing in Visual Basic).

Because the OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName has an implicit conversion to System.String, and it converts to the expanded text of the qualified name (OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName.ExpandedText), in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use the returned OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName in any place where expanded text of a qualified name (a string) is expected as input, and the corresponding expanded text will be taken automatically from the qualified name.

Also, because the OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElement has an implicit conversion from OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use the returned OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName (containing a target qualified name, which becomes the "any hierarchical" forward reference) in any place where OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElement is expected as input, and the corresponding OPC UA browse path element will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the OpcLabs.EasyOpc.UA.Navigation.UABrowsePathElement.FromUAQualifiedName static method instead.

Also, because the UAReadParameters has an implicit conversions from OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply the returned OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName (representing the name of the encoding to be used) in any place where UAReadParameters is expected as input, and the corresponding OPC UA read parameters will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the UAReadParameters.FromDouble or UAReadParameters.FromUAQualifiedName static method instead.

Remarks

Because the OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName has an implicit conversion from System.String, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a string (representing the expanded text of the qualified name) in place of OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName value when setting this property, and the corresponding OPC UA qualified name will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName.UAQualifiedName Constructor(String) constructor instead.

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