Zeroconf.ZeroconfHost.AddService (Zeroconf.IService service) Null Key Exception - iOS, Bug

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Using latest stable Zeroconf 3.6.11
I am trying to get an iOS Xamarin project working for iOS 14.5+ (previously worked on iOS versions prior). It only needs to search for a single service and so I have followed the instructions for adding NSBonjourServices in the Info.plist:

<key>NSLocalNetworkUsageDescription</key>
	<string>Looking for printers with mDNS/Bonjour services</string>
<key>NSBonjourServices</key>
	<array>
		<string>_printer._tcp</string>
	</array>

When calling ZeroconfResolver.ResolveAsync("_printer._tcp.local.") the following exception bubbles up from Zeroconf.ZeroconfHost.AddService (Zeroconf.IService service):

{System.ArgumentNullException: Value cannot be null.Parameter name: key at System.Collections.Generic.Dictionary2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) [0x00008] in <35fb05e83cf64d249b5a7be1a6f7838a>:0 at System.Collections.Generic.Dictionary2[TKey,TValue].set_Item (TKey key, TValue value) [0x00000] in <35fb05e83cf64d249b5a7be1a6f7838a>:0 at Zeroconf.ZeroconfHost.AddService (Zeroconf.IService service) [0x00000] in //Zeroconf/ZeroconfRecord.cs:193 at Zeroconf.BonjourBrowser.RefreshZeroconfHostDict () [0x00121] in //Zeroconf/BonjourBrowser.cs:436 at Zeroconf.BonjourBrowser.ReturnZeroconfHostResults () [0x00028] in //Zeroconf/BonjourBrowser.cs:361 at Zeroconf.ZeroconfNetServiceBrowser.ResolveAsync (Zeroconf.ResolveOptions options, System.Action1[T] callback, System.Threading.CancellationToken cancellationToken, System.Net.NetworkInformation.NetworkInterface[] netInterfacesToSendRequestOn) [0x0010b] in /_/Zeroconf/ZeroconfNetServiceBrowser.cs:39 at Zeroconf.ZeroconfResolver.ResolveAsync (Zeroconf.ResolveOptions options, System.Action1[T] callback, System.Threading.CancellationToken cancellationToken, System.Net.NetworkInformation.NetworkInterface[] netInterfacesToSendRequestOn) [0x000e0] in //Zeroconf/ZeroconfResolver.Async.cs:105 at Zeroconf.ZeroconfResolver.ResolveAsync (System.Collections.Generic.IEnumerable1[T] protocols, System.TimeSpan scanTime, System.Int32 retries, System.Int32 retryDelayMilliseconds, System.Action1[T] callback, System.Threading.CancellationToken cancellationToken...

ZeroconfResolver.IsiOSWorkaroundEnabled resolves to true.

I am trying to run the demo iOS project included in the repo to confirm similar behavior, but I currently can get it working... it builds and deploys, but is just a black screen.

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So the exception comes from here:

Zeroconf/Zeroconf/ZeroconfRecord.cs

Line 193 in 238df25

services[service.ServiceName] = service ?? throw new ArgumentNullException(nameof(service));

The ServiceName on the Service object is not being set (is null) as part of the iOS pipeline of the ResolveAsync. I will see if I can figure out where the ServiceName is supposed to be set, but isn't - Nullable enabled would be helpful here.

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I am thinking it should have been set about here in the BonjourBrowser.cs

Zeroconf/Zeroconf/BonjourBrowser.cs

Lines 399 to 402 in 238df25

	Service svc = new Service();
	svc.Name = GetNsNetServiceName(nsNetService);
	svc.Port = (int)nsNetService.Port;
	// svc.Ttl = is not available

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@clairernovotny Please review #246