.NET / C# Feature Flags

Feature flag / toggle management built for .NET and C# apps

Feature flags are a software development best practice of gating functionality. Functionality can be deployed “off”, then turned on via the feature flag, separate from deployment. With feature flags, you can manage the entire lifecycle of a feature.

LaunchDarkly's .NET SDK lets you create and maintain .NET/C# feature flags across your entire application. You can centrally manage all of your feature flags, perform granular rollouts, and kill bad features without redeploying. All flag values are evaluated in-memory, so there is no latency for your users. New flag settings are streamed to the SDKs in real-time, so any changes to your flag rules will take effect almost immediately.

LaunchDarkly Dashboard & Feature Flag Manager
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Here are some product benefits of LaunchDarkly's .NET Feature Flag SDK:

  • Real-time feature flags
  • In-memory flag evaluation with near zero latency
  • No external HTTP calls for flag values
  • Boolean & multivariate feature flags
  • Custom percentage rollouts and targeting rules
  • A/B testing
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Flag management benefits:

  • Audit log
  • Custom roles
  • Custom webhooks
  • Integrations for Slack and HipChat

.NET Feature Flags

Let's create a .NET feature flag for a "One Click Checkout"

1.Use NuGet to add the SDK to your project

Check out our open source .NET SDK on GitHub or read through the reference documentation.

       Install-Package LaunchDarkly.Client

2.Create a new LaunchDarkly client

       LdClient client = new LdClient("YOUR_SDK_KEY");

3.Create a feature flag in LaunchDarkly

A flag allows you to manage a feature from the LaunchDarkly dashboard.

4.Wrap your code with a feature flag

First, create a user.  You can pass us any data about users for targeting and segmentation. 
Then, call variation and see whether the flag is on for that user.

        User user = User.WithKey("bob@example.com")
          .AndCustomAttribute("groups", "beta_testers");
        bool showFeature = await client.variation("one_click_checkout", user, false);
        if (showFeature) {
          // Show One Click Checkout
        else {
          // the code to run if the feature is off

5.Manage your flag

Use LaunchDarkly to determine which users see the feature.
You can roll out to a percentage of your users or target individual users/groups.

Create your own .NET feature flags in minutes.
How It Works