NSNumber numberWithInt：返回奇怪的数字？
我刚刚开始使用核心数据，遇到了一个问题，我需要使用适当的 ID 保存新对象。
我试图添加行中的下一个数字作为用户添加的对象的 ID：
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:[NSEntityDescription entityForName:@"Favorites" inManagedObjectContext:managedObjectContext]];
[request setIncludesSubentities:NO];
NSError *err;
NSUInteger count = [managedObjectContext countForFetchRequest:request error:&err];
NSManagedObjectContext *context = [fetchedResultsController managedObjectContext];
NSEntityDescription *entity = [[fetchedResultsController fetchRequest] entity];
NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];
[newManagedObject setValue:[NSNumber numberWithInt:count] forKey:@"favoritesID"];
如果我然后去获取 valueForKey:@"favoriteID" 我会得到类似“81933072”的内容，这是错误的。
我检查了 count ，它是正确的数字，只是当我将它放入 Core Data 时，它变成了其他东西。顺便说一句，favoriteID 是一个 int16。
I am just starting out with Core Data and ran into an issue where I need to save the new object with the appropriate ID.
I'm trying to add the next number in the row as an ID for the object the user adds:
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:[NSEntityDescription entityForName:@"Favorites" inManagedObjectContext:managedObjectContext]];
[request setIncludesSubentities:NO];
NSError *err;
NSUInteger count = [managedObjectContext countForFetchRequest:request error:&err];
NSManagedObjectContext *context = [fetchedResultsController managedObjectContext];
NSEntityDescription *entity = [[fetchedResultsController fetchRequest] entity];
NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];
[newManagedObject setValue:[NSNumber numberWithInt:count] forKey:@"favoritesID"];
If I then go and get the valueForKey:@"favoriteID" I get something like "81933072", which is wrong.
I have checked count and it's the correct number, it's just when I put it into Core Data that it becomes something else. favoriteID is an int16 btw.
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valueForKey：将返回 NSNumber，而不是整数。您需要对其调用
[myNumber integerValue]。编辑：那么您要将 NSNumber 分配给 int16 吗？那是行不通的。您应该更改变量类型。
valueForKey: will return the NSNumber, not an integer. You need to call
[myNumber integerValue]on it.Edit: So you're assigning an NSNumber to an int16? That's not gonna work. You should change your variable type.