cocoa - Iterate through NSManagedObjectContext objects? -

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i want iterate through of objects in nsmanagedobjectcontext, , update them manually. then, every managed object should updated. what's best way this?

theoretically iterate through entity descriptions in managed object model, build no-predicate fetch request them, loop on returned objects , update. example:

// given nsmanagedobjectcontext *context nsmanagedobjectmodel *model = [[context persistentstorecoordinator]                                managedobjectmodel]; for(nsentitydescription *entity in [model entities]) {     nsfetchrequest *request = [[[nsfetchrequest alloc] init] autorelease];     [request setentity:entity];     nserror *error;     nsarray *results = [context executefetchrequest:request error:&error];     // error-checking here...     for(nsmanagedobject *object in results) {         // updates here     } }

note can cast nsmanagedobjects returned necessary either testing class equality (using iskindofclass: or related method) or figuring out class current entity (using managedobjectclassname property on entity in conjunction nsclasswithname() method).


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