Bug 7986 - Cannot easily roundtrip CBUUID.ToString() and CBUUID.FromString()
Summary: Cannot easily roundtrip CBUUID.ToString() and CBUUID.FromString()
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: 6.0.x
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Sebastien Pouliot
Depends on:
Reported: 2012-10-25 10:52 UTC by Kirk Klobe
Modified: 2012-11-06 17:12 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Kirk Klobe 2012-10-25 10:52:39 UTC
The CoreBluetooth pattern of saving a discovered peripheral's UUID for future reconnection using [CBCentralManager retrievePeripherals] is a bit clunky given the current MonoTouch API surface. It appears that I either have to p/invoke CFUUIDCreateString() or do string fiddling along the lines of:

var uuidString = CBUUID.FromCFUUID(e.peripheral.UUID).ToString ();
var start = uuidString.IndexOf ("<");
var end = uuidString.IndexOf (">");
var guid = uuidString.Substring(start + 1, end - start - 1).Replace (" ","");
var validGuid = guid.Insert (8, "-").Insert (13,"-").Insert (18,"-").Insert (23,"-");

It would be convenient to have a built-in way of getting a string from a CBUUID that can be fed right back into CBUUID.FromString().
Comment 1 Sebastien Pouliot 2012-11-06 08:56:04 UTC
I'm not sure CFUUIDCreateString would help. Apple documentation does not state that CBUUID and CFUUID are tool-free bridged. 

It could be missing (documentation) but CFUUID and NSUUID are documented not to be toll free _and_ there's an API to create a CBUUID from a CFUUID (which would not be needed).

OTOH easy roundtripping is something we should provide.
Comment 2 Kirk Klobe 2012-11-06 09:03:44 UTC
I mentioned CFUUIDCreateString because that is how Apple does it with their TemperatureSensor example:


Thanks for responding and considering it!
Comment 3 Sebastien Pouliot 2012-11-06 17:12:13 UTC
ToString was overriden so it can be used to roundtrip. The old string value is still available with the `Description` property.

There's also a ToString overload that takes a boolean, when using `true` it will "promote" a 16bits UUID into a 128bits UUID, otherwise (false, default), the original size will be kept.

Fixed in
ios6: 028d3e6bd8c056bf1be78b4ac9f789277d413af6
master: 0f3437a42e9382f4c4472488c5472d6344d2aeb9