Question

I am trying to parse a json string straight into a managed object.
The json string contains all strings, but my Entity has Date objects.

if this is my json string

{
"name":"John",
"dob": "12/12/2008",
etc...
}

and here’s my entity Person:

name : NSString
dob: Date
etc...

I want to parse that json straight through by looping through the keys of the Json dict, and setting the values to the matching keys of my entity:

Person *aPerson = [NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:managedObjectContext];
NSArray *keys = [jsonDict allKeys];

for (NSString *key in keys) {

 [aPerson setValue:[jsonDict valueForKey:key] forKey:key];

}

This only works if all my entity’s properties are NSStrings.

How can I get the type/class of my entity’s property to be able to set the various types?

eg.
if key = @”dob”
how can I get the type/class of aPerson.dob?

so my code will look something like:

Person *aPerson = [NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:managedObjectContext];
NSArray *keys = [jsonDict allKeys];

for (NSString *key in keys) {
    if([[aPerson objectForKey:key] isKindOfClass:[NSDate class]])
    {
       // Create an NSDate object
    }else{
       [aPerson setValue:[jsonDict valueForKey:key] forKey:key];
    }
}

thanks

UPDATE:

Ok I tried using the isKindOfClass and here’s the result was:

// for key = @"name" 
// aPerson.name is NSString
[[aPerson valueForKey:key] isKindOfClass:[NSString class]] => TRUE
[[aPerson valueForKey:key] isKindOfClass:[NSObject class]] => TRUE

// for key = @"age"
// aPerson.age is NSNumber
[[aPerson valueForKey:key] isKindOfClass:[NSNumber class]] => TRUE
[[aPerson valueForKey:key] isKindOfClass:[NSObject class]] => TRUE

// for key = @"dob"
// aPerson.dob is NSDate
[[aPerson valueForKey:key] isKindOfClass:[NSDate class]] => FALSE
[[aPerson valueForKey:key] isKindOfClass:[NSObject class]] => FALSE

how is that?
@dynamic dob and NSDate, is notOfClass NSDate!

please tell me what I am missing!

Answer 1

Thanks a lot to Rog, for sending me in the right direction, I ended up overriding my setter as below:

-(void)setDob:(id)value
{
    [self willAccessValueForKey:@"dob"];
    if ([value isKindOfClass:[NSString class]]) {
        [self setPrimitiveValue:[DateFormatter dateFromString:value] forKey:@"dob"];
    }else{
        [self setPrimitiveValue:value forKey:@"dob"];
    }
    [self didChangeValueForKey:@"dob"];
}

and all works great now, instead of a 1000 lines of code parsing, it’s all done in 3!
nice one!