Add backward compatibility when serializing enums to json

[vfisher]

No backward compatibility with old version of superobject, when serializing enums. Version in this repo can handle both name and integer value of enum. Old version can handle only integer value. Can you please add {$DEFINE ...}, that will change behavior of converting enum to json to integer value for backward compatibility with old versions. Applications, that was compiled in old versions, will parse this json successfully.

What i mean:

Type TEnum = (teOne = 0, teTwo = 1, teThree = 2, teFour = 3); TRecrd = Record e: TEnum; End;

...

Var s,: String; r: TRecrd; ACTX: TSuperRttiContext; begin ACTX:= TSuperRttiContext.Create; try s:= '{"e": "teThree"}'; r:= ACTX.AsType(SO(s)); // works only in current version. Old versions will fail with 'Marshalling error' s:= '{"e": 3}'; r:= ACTX.AsType(SO(s)); // works in both old and current version finally ACTX.Free; end; end;

[pult]

r := ACTX.AsType<TRecord>( SO('{"e": "teThree"}') ); Serialization or deserialization? Your sample - it is deserealizatioin. Specify which old version? It is not clear what is wrong with the fact that deserialization "enum-name" works correctly?

[vfisher]

It's not a bug. It's feature request. :) Old version can't deserialize enums, that stored in json like, for example, {"enum_value":"etOne"}, but works ok with {"enum_value":1}.

So, if I take this version on superobject, serialize some enum to json and give it to software, that was written with obsolette version of so, it will fails.

If there be a some DEFINE in your version of superobject, that can override behavior of serializing enums, like in old version (integers), than result json with enums will became compatible with old version.

Which old version? I have no idea, we use it many years. Changelog begins with "v1.2" and no other version info in sources.

[pult]

Show how you serialize (generate json-text). In the example, only deserialization.

[pult]

SuperRttiContextDefault.ForceEnumeration := False;
ACTX :=SuperRttiContextDefault;

or 
ACTX: TSuperRttiContext;
ACTX := SuperRttiContextClassDefault.Create; // or TSuperRttiContext.Crerate;
ACTX.ForceEnumeration := False;

[vfisher]

Exactly what is needed! Thanks!