The core logic is implemented as a PCL, but due to networking APIs being platform-specific, a platform-specific helper library is required. Just make sure that you also install the NuGet to your main app and you'll be all set.

The easiest way to get started is to use the NuGet package.

Install-Package Zeroconf

Current Build Status:

There's are two methods with a few optional parameters:

using Zeroconf;
public async Task ProbeForNetworkPrinters()
{
    IReadOnlyList<IZeroconfHost> results = await
        ZeroconfResolver.ResolveAsync("_printer._tcp.local.");
}

public async Task EnumerateAllServicesFromAllHosts()
{
    ILookup<string, string> domains = await ZeroconfResolver.BrowseDomainsAsync();            
    var responses = await ZeroconfResolver.ResolveAsync(domains.Select(g => g.Key));            
    foreach (var resp in responses)
        Console.WriteLine(resp);
}

The ResolveAsync method has one required and several optional parameters. The method signature is as follows:

Task<IReadOnlyList<IZeroconfHost>> ResolveAsync(string protocol, TimeSpan scanTime = default(TimeSpan), int retries = 2, int retryDelayMilliseconds = 2000, Action<IZeroconfHost> callback = null, CancellationToken cancellationToken = default(CancellationToken));

The BrowseDomainsAsync method has the same set of optional parameters. The method signature is:

Task<ILookup<string, string>> BrowseDomainsAsync(TimeSpan scanTime = default (TimeSpan), int retryDelayMilliseconds = 2000, Action<string, string> callback = null, CancellationToken cancellationToken = default (CancellationToken))

What you get back from the Browse is a lookup, by service name, of a group that contains every host offering that service. Thst most common use would be in the example above, passing in all keys (services) to the Resolve method. Otherwise, you can also see what hosts are offering which services as well.

Starting in v2.5, there are two additional methods that return IObservable's instead of Tasks. These methods are otherwise identical to the *Async versions but are more suitable for some usages.

The ResolveAsync method is thread-safe, however all calls to it are serialized as only one can be in-progress at a time.

There is currently a bug on Xamarin.Android 4.x that incorrectly strips out internal Socket methods. This has been fixed for the Xamarin.Android 5.0 series. As a workaround on 4.x, entering System; in to the Ignore Assemblies field in the Project Options->Build->Android Build page will fix the problem.

This library was made possible through the efforts of the following projects:

• ZeroconfRT by Sergey Aldoukhov
• DNS.NET Resolver by Alphons van der Heijden