OPC Studio User's Guide and Reference
UAValueRanks Class
Members 



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA Namespace : UAValueRanks Class
Contains standard OPC-UA value rank values. The value rank indicates whether the Value Attribute of the OPC-UA Variable is an array and how many dimensions the array has.
Syntax
'Declaration
 
<ComVisibleAttribute(False)>
Public MustInherit NotInheritable Class UAValueRanks 
'Usage
 
Dim instance As UAValueRanks
[ComVisible(false)]
public static class UAValueRanks 
[ComVisible(false)]
public ref class UAValueRanks abstract sealed 
Remarks

OPC UA defines a value rank that differs from the common understanding of array rank. Scalars have OPC UA value rank of -1 (not 0), and there are other special value ranks defined.

Value rank specifies if the Value Attribute of an OPC-UA Variable is an array, and if so, the number of dimensions it has. This class provides constants representing different value ranks as defined by OPC-UA, facilitating the interpretation and handling of variable value ranks within OPC-UA applications.

The OPC UA value rank values are summarized in the following table. The "Array ranks" column contains the corresponding value or values of the array rank in its traditional meaning.

OPC UA value rank Symbolic name Description Array rank
-3 ScalarOrOneDimension The variable may be a scalar or a one dimensional array. 0 or 1
-2 Any The variable may be a scalar or an array of any dimension. 0, 1, 2, ...
-1 Scalar The variable is always a scalar. 0
0 OneOrMoreDimensions The variable is always an array with one or more dimensions. 1, 2, 3, ...
1 OneDimension The variable is always one dimensional array. 1
2 TwoDimensions The variable is always an array with two dimensions. 2
3, 4, 5, ... The variable is always an array with the specified number of dimensions. 3, 4, 5, ...

OPC UA value ranks 3 and higher do not have symbolic names in this class, but they are still valid.

Inheritance Hierarchy

System.Object
   OpcLabs.EasyOpc.UA.UAValueRanks

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