Question

I’m trying to map a dictionary of strings from a JSON fetch to a KVC compliant NSManagedObject, I can successfully use setValue: forKey: but i fail to see how I can map types.

For example I shouldn’t be able to set a date to any random string: Printing description of myDate:
asdfsadf
however it worked.

I had a look at https://stackoverflow.com/a/5345023/828859 which provided some useful answers. I can go in and create validation for every single property… but that doesn’t seem very DRY because ill have to validate every date and set the out value separately each time i have a date.

I would prefer to mutate by type before I use setValue: forKey: but I don’t know how to discriminate on the property type.

What I want to do:

switch([object typeforkey:key]){
   case @"NSDate":
   //...
   value = mutatedDate
   //...
}
[object setValue:value forKey:key];

Answer 1

I ended up using another dictionary for property type mapping. Then a object mapping object checks the object to be map abides by this particular protocol and uses the property type dictionary to convert each property before using setValue:forKey:.