Question

I keep getting this following DCC error, published field ‘name’ is not a class or interface type for the following class.

  TGroup = class
    name:string[32]; <<<========================
    rwFeatures:TFeatures;
    roFeatures:TFeatures;
    levels:TLevels;   
  private

  public
    constructor Create;
    procedure Read(var f:file);
    procedure ReadOld(var f:file);
    procedure Write(var f:file);   
  end;

What does it mean?

Answer 1

The class is compiled with the Emit runtime type information setting enabled. When the class is compiled with runtime type information, the default visibility is published. Which means that the short string field is published. And short string fields are not allowed to be published.

The documentation says:

Fields can be published only if they are of a class or interface type.

That’s a pretty stringent requirement. It means that you can’t publish integer or boolean fields, for example.

I suspect this limitation is because the primary use for published fields is for object references. Think of the components on a form.

Solve the problem using one of these options:

1. Don’t emit runtime type information for this class.
2. Make the short string fields public rather than published.
3. Use properties rather than fields.