how do I keep the map key as number

[jianyunli]

I used map() for my ES6 Map myField, looks like it converted key to strings, how can I keep it as the number?

createModelSchema(MyClass, { myField: map() })

[Lechros]

I extended custom with list to support dictionary primitive key/any PropSchema values. Map<K, V> =serializer=> [K, V][] =deserializer=> Map<K, V>

[NaridaL]

Was the actual key being converted to string, or were the types wrong?

[Lechros]

It is converted to JS object, which only supports string key.

[NaridaL]

Right.. map converts to a JSON object which has string keys. You can use afterDeserialize to fix this if it simple but the recommended approach is to use mapAsArray which is made for this case explictly:

https://github.com/mobxjs/serializr/blob/master/src/types/mapAsArray.ts

For ES6 maps this has the benefit of being allowed to have non-string keys in the map.