Does NSJSONSerialization deserialize numbers as NSDecimalNumber?

Question

Take the following piece of code:

NSError *error;
NSString *myJSONString = @\"{ \\\"foo\\\" : 0.1}\";
NSData *jsonData = [myJSONString dataUsingEncoding:NSUTF8St         


        

Answer 1

To answer the question in the title: No, it doesn't, it creates NSNumber objects. You can easily test this:

NSArray *a = @[[NSDecimalNumber decimalNumberWithString:@"0.1"]];
NSData *data = [NSJSONSerialization dataWithJSONObject:a options:0 error:NULL];
a = [NSJSONSerialization JSONObjectWithData:data options:0 error:NULL];
NSLog(@"%@", [a[0] class]);

will print __NSCFNumber.

You can convert that NSNumber object to an NSDecimalNumber with [NSDecimalNumber decimalNumberWithDecimal:[number decimalValue]], but according to the docs for decimalValue

The value returned isn’t guaranteed to be exact for float and double values.