Unified Automation Forum

Posted: **16 Jul 2021, 14:36**

Hi,
I'm trying to read structure with client. I'm using the client_cpp_sdk project.
I'm using OPC UA Demo Server.
Particullary, I'm trying to read the Variable (CarExtras under Root->Objects->Demo->000_Static->Scalar->Structures) with Identifier = Demo.Static.Scalar.CarExtras IdentifierType = String, NamespaceIndex = 2.
In UAExpert I see that the Node is a structure with 4 field: [0] air conditioner, [1] super charged, [2] launch control, [3] navigation system.
Using client_cpp_sdk example, I see that the same structure CarExtras has 2 fields with the name Value and ValidBits.
Why is the same structure seen in two different ways?

Thanks,
Lorenzo

Posted: **19 Jul 2021, 21:19**

Hello Lorenzo,

the DataType CarExtras is an OptionSet. UaExpert shows all options (so that they can also be written).

The console client just show the seleced options.
option on index 0 and 4 is turned off.
option[1] (super charged) and option[2] (launch control) is set -> value is 6
ValidBits is 0x0F because all fields have a meaning and can be used by the client.

This is all correct so far - however the output is not easy to read. That is why we changed the output for OptionSets in the console client. It will be available in the next service release:

Code: Select all

void printGenericOptionSetValue(const UaGenericOptionSetValue& value)
{
    UaOptionSetDefinition definition = value.optionSetDefinition();
    for (int i = 0; i < definition.childrenCount(); i++)
    {
        UaLocalizedText field = definition.child(i);
        // Get field name
        UaString sFieldName = field.toString();
        // Get field value
        UaVariant vFieldValue = value.value(i);
        printf("    [%d] %s = %s\n", i, sFieldName.toUtf8(), vFieldValue.toString().toUtf8());
    }
}

result:

Code: Select all

** UaSession::read result **************************************
  Variable Demo.Static.Scalar.CarExtras with value:
    [0] air conditioner = false
    [1] super charged = true
    [2] launch control = true
    [3] navigation system = false
****************************************************************

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Client SDK: Reading Structure

Client SDK: Reading Structure

Re: Client SDK: Reading Structure