.NET Client SDK

Set up the SDK

1. Install the SDK

   The package is hosted on Nuget. Install it from your Visual Studio's Nuget package manager, or through the NuGet CLI:

   shell

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   nuget install Statsig
   

2. Initialize the SDK

   Next, initialize the SDK with a client SDK key from the "API Keys" tab on the Statsig console. These keys are safe to embed in a client application.Along with the key, pass in a User Object with the attributes you'd like to target later on in a gate or experiment.

   csharp

   Copy

   using Statsig;
   using Statsig.Client;
   
   await StatsigClient.Initialize(
       "client-sdk-key",
       new StatsigUser { UserID = "some_user_id", Email = "user@email.com" },
       new StatsigOptions(new StatsigEnvironment(EnvironmentTier.Development)) // optional, use when needed to customize certain behaviors
   );
   

Use the SDK

Checking a Feature Flag/Gate

if (StatsigClient.CheckGate("new_homepage_design"))
{
  // Gate is on, show new home page
}
else
{
  // Gate is off, show old home page
}

Reading a Dynamic Config

Feature Gates are useful for simple on/off switches with optional advanced user targeting. To send a different set of values (strings, numbers, etc.) to clients based on specific user attributes such as country, use Dynamic Configs. The API is similar to Feature Gates, but you get a complete JSON object you can configure on the server and fetch typed parameters from it. For example:

DynamicConfig config = StatsigClient.GetConfig("awesome_product_details");

// The 2nd parameter is the default value to be used in case the given parameter name does not exist on
// the Dynamic Config object. This can happen when there is a typo, or when the user is offline and the
// value has not been cached on the client.
string itemName = config.Get<string>("product_name", "Awesome Product v1");
double price = config.Get<double>("price", 10.0);
bool shouldDiscount = config.Get<bool>("discount", false);

Getting a Layer/Experiment

// Values via getLayer

Layer layer = StatsigClient.GetLayer("user_promo_experiments");
var promoTitle = layer.Get("title", "Welcome to Statsig!");
var discount = layer.Get("discount", 0.1);

// or, via getExperiment

DynamicConfig  titleExperiment = StatsigClient.GetExperiment("new_user_promo_title");
DynamicConfig  priceExperiment = StatsigClient.GetExperiment("new_user_promo_price");

var promoTitle = titleExperiment.Get("title", "Welcome to Statsig!");
var discount = priceExperiment.Get("discount", 0.1);

...

double price = msrp * (1 - discount);

Logging an Event

After setting up a Feature Gate or Experiment, you may want to track custom events to see how new features or experiment groups affect those events. Call the Log Event API for the event. You can also provide a value and metadata object to be logged with the event:

StatsigClient.LogEvent(
    "add_to_cart",
    "SKU_12345",
    new Dictionary<string, string>() {
        { "price", "9.99" },
        { "item_name", "diet_coke_48_pack" }
    }
);

Statsig User

You need to provide a StatsigUser object to check/get your configurations. Pass as much information as possible to take advantage of advanced gate and config conditions.

Besides userID, Statsig also supports email, ip, userAgent, country, locale and appVersion as top-level fields on StatsigUser. In addition, you can pass any key-value pairs in an object/dictionary to the custom field and create targeting based on them.

After the user logs in or their attributes change, call updateUser with the updated userID and any other updated user attributes:

// if you want to update the existing user, or change to a different user, call updateUser

await StatsigClient.UpdateUser(
    new StatsigUser { UserID = "new_user_id", Email = "new_user@email.com" },
);

Private Attributes

To prevent sensitive user PII from being logged, use the privateAttributes field on the StatsigUser object. Statsig uses attributes set in privateAttributes only for evaluation and targeting, then removes them from any logs before sending them to the server.

For example, if you have feature gates that pass only for users with emails ending in "@statsig.com" but don't want to log your users' email addresses to Statsig, add the key-value pair { email: "my_user@statsig.com" } to privateAttributes on the user.

Statsig Options

Initialize() takes an optional parameter options in addition to sdkKey and user that you can provide to customize the Statsig client.

Shutting Statsig Down

The SDK keeps event logs in the client cache and flushes them periodically to save data and battery usage. Because of this, some events may not have been flushed when your app shuts down.

To ensure all logged events are flushed or saved locally, shut down Statsig when your app is closing:

StatsigClient.Shutdown();

FAQs

How do I run experiments for logged out users?