OPC Studio User's Guide and Reference
ValueAge Property (DAReadParameters)



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.DataAccess Namespace > DAReadParameters Class : ValueAge Property
Determines the age of value you would like to obtain (in milliseconds).
Syntax
'Declaration
 
<DataMemberAttribute()>
<UnitAttribute("ms")>
Public Property ValueAge As Integer
'Usage
 
Dim instance As DAReadParameters
Dim value As Integer
 
instance.ValueAge = value
 
value = instance.ValueAge
[DataMember()]
[Unit("ms")]
public int ValueAge {get; set;}
[DataMember()]
[Unit("ms")]
public:
property int ValueAge {
   int get();
   void set (    int value);
}

Property Value

Unit of measurement is ms.

The default value of this property is 1000.

Exceptions
ExceptionDescription

The value of an argument is outside the allowable range of values as defined by the invoked method.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Remarks

This value is significant only when the DataSource property is set to ByValueAge.

The value must be greater than or equal to zero, or it must be equal to System.Threading.Timeout.Infinite.

When the value is System.Threading.Timeout.Infinite, the value will always be provided from the memory, i.e. without actually accessing the OPC server.

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