String Bus Element doesn't work

I created a struct and a bus from the struct. I can create it correctly but it is not usable in a Constant block

% Create Model Struct
car.id = 1;
car.type = "long";

% Create Estimation Data Bus for Simulink Model
car_bus_info = Simulink.Bus.createObject(car);
car_bus = evalin('base', car_bus_info.busName);

The bus is correctly created in Type Editor

Constant value is car

and the type is Bus: car_bus

But I got this error:

Error:Invalid setting in 'DTFoilWinding/Constant10' for parameter 'Value'.

This only happens with string Bus elements. If I don't use car.type, is works

Answer 1

[Walter Roberson]

You need a String Constant block; https://www.mathworks.com/help/simulink/slref/stringconstant.html as regular Constant Block does not support strings.

[Furkan]

String Constant blocks accept only strings, but I need a constant block that supports a bus which includes a string bus element. I can't remove that field from the bus because I read structs from json and they have string fields.

Is there any example that a string bus element is used in a bus creator or a bus selector?