# register()

A function that registers a placement that can be remotely configured to show a paywall and gate feature access.

> **Warning**

**Deprecated SDK**We strongly recommend migrating to the new [Superwall Expo SDK](/docs/expo), see our [migration guide](/docs/expo/guides/migrating-react-native) for details.



Purpose [#purpose]

Registers a placement so that when it's added to a campaign on the Superwall Dashboard, it can trigger a paywall and optionally gate access to a feature.

Signature [#signature]

```typescript
async register(params: {
  placement: string
  params?: Map<string, any> | Record<string, any>
  handler?: PaywallPresentationHandler
  feature?: () => void
}): Promise<void>
```

Parameters [#parameters]

<TypeTable
  type="{
  placement: {
    type: &#x22;string&#x22;,
    description: &#x22;The name of the placement you wish to register.&#x22;,
    required: true,
  },
  params: {
    type: &#x22;Map<string, any> | Record<string, any>?&#x22;,
    description: &#x22;Optional parameters to pass with your placement. These can be referenced within audience filters in your campaign. Keys beginning with `$` are reserved for Superwall and will be dropped. Arrays and dictionaries as values are not supported and will be omitted.&#x22;,
    default: &#x22;undefined&#x22;,
  },
  handler: {
    type: &#x22;PaywallPresentationHandler?&#x22;,
    description: &#x22;A handler whose functions provide status updates for the paywall lifecycle.&#x22;,
    default: &#x22;undefined&#x22;,
  },
  feature: {
    type: &#x22;(() => void)?&#x22;,
    description: &#x22;An optional completion callback representing the gated feature. It is executed based on the paywall's gating mode: called immediately for **Non-Gated**, called after the user subscribes or if already subscribed for **Gated**. If not provided, you can chain a `.then()` block to the returned promise.&#x22;,
  },
}"
/>

Returns / State [#returns--state]

Returns a Promise that resolves when registration completes. If you supply a `feature` callback, it will be executed according to the paywall's gating configuration, as described above.

Usage [#usage]

With feature callback:

```typescript
Superwall.shared.register({
  placement: "premium_feature",
  params: {
    source: "onboarding"
  },
  feature: () => {
    // Code that unlocks the premium feature
    openPremiumScreen()
  }
})
```

Using promise chaining:

```typescript
await Superwall.shared.register({
  placement: "premium_feature",
  params: {
    source: "onboarding"
  }
}).then(() => {
  // Code that unlocks the premium feature
  openPremiumScreen()
})
```

With presentation handler:

```typescript
import { PaywallPresentationHandler } from "@superwall/react-native-superwall"

const handler = new PaywallPresentationHandler()
handler.onPresent((info) => {
  console.log("Paywall presented:", info.name)
})
handler.onDismiss((info, result) => {
  console.log("Paywall dismissed:", result)
})

Superwall.shared.register({
  placement: "onboarding_complete",
  params: {
    source: "onboarding"
  },
  handler: handler
})
```

Behavior [#behavior]

This behavior is remotely configurable via the Superwall Dashboard:

* For **Non-Gated** paywalls, the feature callback is executed when the paywall is dismissed or if the user is already paying.
* For **Gated** paywalls, the feature callback is executed only if the user is already paying or if they begin paying.
* If no paywall is configured, the feature callback is executed immediately.
* If no feature callback is provided, the returned promise resolves when registration completes.
* If a feature callback is provided, the returned promise always resolves after the feature callback is executed.

Note: The feature callback will not be executed if an error occurs during registration. Such errors can be detected via the `handler`.