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    dotnet add package growthbook-c-sharp

Quick Usage

This library is based on the GrowthBook SDK specs and should be compatible with the usage examples in the GrowthBook docs.

Down below you'll find two basic examples on how the package works.


  1. Declare features

    var staticFeatures = new Dictionary<string, Feature>
    {"firstFeature", new Feature{ DefaultValue = true}},
    {"secondFeature", new Feature{ DefaultValue = false}}
  2. Create a context and add the features

    var context = new Context
    Enabled = true,
    Url = "",
    Features = staticFeatures
  3. Create the GrowthBook object with the context

    using GrowthBook;

    var GrowthBook = new GrowthBook.GrowthBook(context);
  4. Check whether a feature is enabled

    GrowthBook.IsOn("firstFeature") // true
    GrowthBook.IsOn("secondFeature") // false

Loading feature definitions from an API

Because feature definitions are typically loaded from API calls or cache, Json.NET objects are used to represent arbitrary document types such as Attributes, Conditions, and Feature values.

To load your features from the GrowthBook API use the following example:

  1. Create a result model for the API response

    public class FeaturesResult
    public HttpStatusCode Status { get; set; }
    public IDictionary<string, Feature>? Features { get; set; }
    public DateTimeOffset? DateUpdated { get; set; }
  2. call the endpoint and deserialize result

    var url = "YOUR_GROWTHBOOK_URL/api/features/YOUR_API_KEY";
    var response = await client.GetAsync(url);

    if (response.IsSuccessStatusCode)
    var content = await response.Content.ReadAsStringAsync();
    var featuresResult = JsonConvert.DeserializeObject<FeaturesResult>(content);
  3. Construct a context and initialize GrowthBook

    var GrowthBook = new GrowthBook.GrowthBook(
    new Context {
    Enabled = true,
    Url = "",
    Features = featuresResult.Features,

Generic getters

To make it easier to deal with Feature values, generic getter functions are provided for the following:

  • Experiment:
    • GetVariations<T>()
  • ExperimentResult:
    • GetValue<T>()
  • Feature:
    • GetDefaultValue<T>()
  • FeatureResult:
    • GetValue<T>()
  • Feature Rule:
    • GetVariations<T>()
  • GrowthBook:
    • GetFeatureValue<T>(string key, T fallback)