diff --git a/en/application-dev/reference/apis/js-apis-emitter.md b/en/application-dev/reference/apis/js-apis-emitter.md
index bb6ff52a02fb33d938f8432b3864185b6b0778d2..8e08290aaefa6b8f52eec4f21f4671b1099d92fc 100644
--- a/en/application-dev/reference/apis/js-apis-emitter.md
+++ b/en/application-dev/reference/apis/js-apis-emitter.md
@@ -8,12 +8,6 @@
import emitter from '@ohos.events.emitter'
```
-## System Capabilities
-
-```javascript
-SystemCapability.Notification.Emitter
-```
-
## Required Permissions
None
@@ -22,25 +16,27 @@ None
Enumerates the event emit priority levels.
-| Name| Value| Description|
+| Name | Value | Description |
| --------- | ---- | ------------------------------------------------- |
-| IMMEDIATE | 0 | The event will be emitted immediately.|
-| HIGH | 1 | The event will be emitted before low-priority events.|
-| LOW | 2 | The event will be emitted before idle-priority events. By default, an event is in LOW priority.|
-| IDLE | 3 | The event will be emitted after all the other events.|
+| IMMEDIATE | 0 | The event will be emitted immediately.
**System capability**: SystemCapability.Notification.Emitter |
+| HIGH | 1 | The event will be emitted before low-priority events.
**System capability**: SystemCapability.Notification.Emitter |
+| LOW | 2 | The event will be emitted before idle-priority events. By default, an event is in LOW priority.
**System capability**: SystemCapability.Notification.Emitter|
+| IDLE | 3 | The event will be emitted after all the other events.
**System capability**: SystemCapability.Notification.Emitter |
## emitter.on
on(event: [InnerEvent](#innerevent), callback: Callback\<[EventData](#eventdata)\>): void
-Subscribes to an event in persistent manner. This method uses a callback to return the event.
+Subscribes to an event in persistent manner. This API uses a callback to return the event.
+
+**System capability**: SystemCapability.Notification.Emitter
**Parameters**
-| Name| Type| Mandatory| Description|
+| Name | Type | Mandatory| Description |
| -------- | ----------------------------------- | ---- | ------------------------ |
-| event | [InnerEvent](#innerevent) | Yes| Event to subscribe to in persistent manner.|
-| callback | Callback\<[EventData](#eventdata)\> | Yes| Callback used to return the event.|
+| event | [InnerEvent](#innerevent) | Yes | Event to subscribe to in persistent manner. |
+| callback | Callback\<[EventData](#eventdata)\> | Yes | Callback used to return the event.|
**Example**
@@ -56,16 +52,18 @@ emitter.on(innerEvent, callback);
## emitter.once
-once(event: [InnerEvent](#innerevent), callback: Callback\<[EventData](#eventdata)\>): **void**
+once(event: [InnerEvent](#innerevent), callback: Callback\<[EventData](#eventdata)\>): void
Subscribes to an event in one-shot manner and unsubscribes from it after the event callback is received.
+**System capability**: SystemCapability.Notification.Emitter
+
**Parameters**
-| Name| Type| Mandatory| Description|
+| Name | Type | Mandatory| Description |
| -------- | ----------------------------------- | ---- | ------------------------ |
-| event | [InnerEvent](#innerevent) | Yes| Event to subscribe to in one-shot manner.|
-| callback | Callback\<[EventData](#eventdata)\> | Yes| Callback used to return the event.|
+| event | [InnerEvent](#innerevent) | Yes | Event to subscribe to in one-shot manner. |
+| callback | Callback\<[EventData](#eventdata)\> | Yes | Callback used to return the event.|
**Example**
@@ -85,11 +83,13 @@ off(eventId: number): void
Unsubscribes from an event.
+**System capability**: SystemCapability.Notification.Emitter
+
**Parameters**
-| Name| Type| Mandatory| Description|
-| ------- | ------ | ---- | -------------- |
-| eventId | number | Yes| Event ID.|
+| Name | Type | Mandatory| Description |
+| ------- | ------ | ---- | ------ |
+| eventId | number | Yes | Event ID.|
**Example**
@@ -103,19 +103,21 @@ emit(event: InnerEvent, data?: EventData): void
Emits an event to the event queue.
+**System capability**: SystemCapability.Notification.Emitter
+
**Parameters**
-| Name| Type| Mandatory| Description|
+| Name| Type | Mandatory| Description |
| ------ | ------------------------- | ---- | -------------- |
-| event | [InnerEvent](#innerevent) | Yes| Event to emit.|
-| data | [EventData](#eventdata) | No| Data carried by the event.|
+| event | [InnerEvent](#innerevent) | Yes | Event to emit. |
+| data | [EventData](#eventdata) | No | Data carried by the event.|
**Example**
```javascript
var eventData = {
data: {
- 'content': "c",
+ "content": "c",
"id": 1,
}};
var innerEvent = {
@@ -129,15 +131,15 @@ emitter.emit(innerEvent, eventData);
Describes an intra-process event.
-| Name| Type| Readable| Writable| Description|
+| Name | Type | Readable| Writable| Description |
| -------- | ------------------------------- | ---- | ---- | ---------------------------------- |
-| eventId | number | Yes| Yes| Event ID, which is used to identify an event.|
-| priority | [EventPriority](#eventpriority) | Yes| Yes| Emit priority of the event.|
+| eventId | number | Yes | Yes | Event ID, which is used to identify an event.
**System capability**: SystemCapability.Notification.Emitter|
+| priority | [EventPriority](#eventpriority) | Yes | Yes | Emit priority of the event.
**System capability**: SystemCapability.Notification.Emitter |
## EventData
Describes the data passed in the event.
-| Name| Type| Readable| Writable| Description|
+| Name| Type | Readable| Writable| Description |
| ---- | ------------------ | ---- | ---- | -------------- |
-| data | [key: string]: any | Yes| Yes| Data carried by the event.|
+| data | [key: string]: any | Yes | Yes | Data carried by the event. The data type can be String, Integer, or Boolean.
**System capability**: SystemCapability.Notification.Emitter|