IsNull Property (DAPropertyId)

Determines whether the property Id is null.

Syntax

[DefaultValue(true)]
public bool IsNull {get;}

[DefaultValue(true)]
public:
property bool IsNull {
   bool get();
}

'Declaration
 
<DefaultValueAttribute(True)>
Public ReadOnly Property IsNull As Boolean

'Usage
 
Dim instance As DAPropertyId
Dim value As Boolean
 
value = instance.IsNull

Remarks

An OPC "Classic" property Id is considered null when its internal value is DAPropertyIds.Null, i.e. equal to -1.

This method or property does not throw any exceptions, aside from execution exceptions such as System.Threading.ThreadAbortException or System.OutOfMemoryException.

Requirements

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

Reference

DAPropertyId Class
DAPropertyId Members

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