51Degrees Device Detection .NET  4.4

Device detection services for 51Degrees Pipeline


This example shows how to use the 51Degrees Cloud service to determine details about a device based on its User-Agent and User-Agent Client Hint HTTP header values.

You will learn:

  1. How to create a Pipeline that uses the 51Degrees cloud service
  2. How to pass input data (evidence) to the Pipeline
  3. How to retrieve the results

This example is available in full on GitHub.

To run this example, you will need to create a resource key. The resource key is used as shorthand to store the particular set of properties you are interested in as well as any associated license keys that entitle you to increased request limits and/or paid-for properties.

You can create a resource key using the 51Degrees Configurator.

Required NuGet Dependencies:

  • FiftyOne.DeviceDetection
  • Microsoft.Extensions.Configuration.Json
  • Microsoft.Extensions.DependencyInjection
  • Microsoft.Extensions.Logging.Console
/* *********************************************************************
* This Original Work is copyright of 51 Degrees Mobile Experts Limited.
* Copyright 2022 51 Degrees Mobile Experts Limited, Davidson House,
* Forbury Square, Reading, Berkshire, United Kingdom RG1 3EU.
* This Original Work is licensed under the European Union Public Licence
* (EUPL) v.1.2 and is subject to its terms as set out below.
* If a copy of the EUPL was not distributed with this file, You can obtain
* one at https://opensource.org/licenses/EUPL-1.2.
* The 'Compatible Licences' set out in the Appendix to the EUPL (as may be
* amended by the European Commission) shall be deemed incompatible for
* the purposes of the Work and the provisions of the compatibility
* clause in Article 5 of the EUPL shall not apply.
* If using the Work as, or as part of, a network application, by
* including the attribution notice(s) required under Article 5 of the EUPL
* in the end user terms of the application under an appropriate heading,
* such notice(s) shall fulfill the requirements of that article.
* ********************************************************************* */
using FiftyOne.Pipeline.CloudRequestEngine.FlowElements;
using FiftyOne.Pipeline.Core.Configuration;
using FiftyOne.Pipeline.Core.FlowElements;
using FiftyOne.Pipeline.Engines.Data;
using FiftyOne.Pipeline.Engines.FiftyOne.FlowElements;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Text;
public class Program
public class Example
public void Run(IServiceProvider serviceProvider, TextWriter output)
var pipelineOptions = serviceProvider.GetRequiredService<PipelineOptions>();
var loggerFactory = serviceProvider.GetRequiredService<ILoggerFactory>();
// In this example, we use the FiftyOnePipelineBuilder and configure it from a file.
// For more information about builders in general see the documentation at
// https://51degrees.com/documentation/_concepts__configuration__builders__index.html
// Create the pipeline using the service provider and the configured options.
using (var pipeline = new FiftyOnePipelineBuilder(loggerFactory, serviceProvider)
// Carry out some sample detections
foreach (var values in ExampleUtils.EvidenceValues)
AnalyseEvidence(values, pipeline, output);
private void AnalyseEvidence(
Dictionary<string, object> evidence,
IPipeline pipeline,
TextWriter output)
// FlowData is a data structure that is used to convey information required for
// detection and the results of the detection through the pipeline.
// Information required for detection is called "evidence" and usually consists
// of a number of HTTP Header field values, in this case represented by a
// Dictionary<string, object> of header name/value entries.
// FlowData is wrapped in a using block in order to ensure that the resources
// are freed in a timely manner.
using (var data = pipeline.CreateFlowData())
StringBuilder message = new StringBuilder();
// list the evidence
message.AppendLine("Input values:");
foreach (var entry in evidence)
message.AppendLine($"\t{entry.Key}: {entry.Value}");
// Add the evidence values to the flow data
// Process the flow data.
message = new StringBuilder();
// Now that it's been processed, the flow data will have been populated with
// the result. In this case, we want information about the device, which we
// can get by asking for a result matching the `IDeviceData` interface.
var device = data.Get<IDeviceData>();
// Display the results of the detection, which are called device properties.
// See the property dictionary at
// https://51degrees.com/developers/property-dictionary
// for details of all available properties.
OutputValue("Mobile Device", device.IsMobile, message);
OutputValue("Platform Name", device.PlatformName, message);
OutputValue("Platform Version", device.PlatformVersion, message);
OutputValue("Browser Name", device.BrowserName, message);
OutputValue("Browser Version", device.BrowserVersion, message);
private void OutputValue(string name,
IAspectPropertyValue value,
StringBuilder message)
// Individual result values have a wrapper called `AspectPropertyValue`.
// This functions similarly to a null-able type. If the value has not been set
// then trying to access the `Value` property will throw an exception.
// `AspectPropertyValue` also includes the `NoValueMessage` property, which
// describes why the value has not been set.
message.AppendLine(value.HasValue ?
$"\t{name}: " + value.Value :
$"\t{name}: " + value.NoValueMessage);
public void Run(PipelineOptions options, TextWriter output)
// Initialize a service collection which will be used to create the services
// required by the Pipeline and manage their lifetimes.
using (var serviceProvider = new ServiceCollection()
// Add the configuration to the services collection.
// Make sure we're logging to the console.
.AddLogging(l => l.AddConsole())
// Add an HttpClient instance. This is used for making requests to the
// cloud service.
// Add the builders that will be needed to create the engines specified in the
// configuration file.
// Get the resource key setting from the config file.
var resourceKey = options.GetResourceKey();
// If we don't have a resource key then log an error.
if (string.IsNullOrWhiteSpace(resourceKey))
$"No resource key specified in the configuration file " +
$"'appsettings.json' or the environment variable " +
$"'{ExampleUtils.RESOURCE_KEY_ENV_VAR}'. The 51Degrees cloud " +
$"service is accessed using a 'ResourceKey'. For more information " +
$"see " +
$"https://51degrees.com/documentation/_info__resource_keys.html. " +
$"A resource key with the properties required by this example can be " +
$"created for free at https://configure.51degrees.com/1QWJwHxl. " +
$"Once complete, populate the config file or environment variable " +
$"mentioned at the start of this message with the key.");
new Example().Run(serviceProvider, output);
static void Main(string[] args)
// Use the command line args to get the resource key if present.
// Otherwise, get it from the environment variable.
string resourceKey = args.Length > 0 ? args[0] :
// Load the configuration file
var config = new ConfigurationBuilder()
// Bind the configuration to a pipeline options instance
PipelineOptions options = new PipelineOptions();
config.Bind("PipelineOptions", options);
// Get the resource key setting from the config file.
var resourceKeyFromConfig = options.GetResourceKey();
var configHasKey = string.IsNullOrWhiteSpace(resourceKeyFromConfig) == false &&
resourceKeyFromConfig.StartsWith("!!") == false;
// If no resource key is specified in the config file then override it with the key
// from the environment variable / command line.
if (configHasKey == false)
new Example().Run(options, Console.Out);