reference/apis-basic-services-kit/js-apis-commonEventManager.md

# @ohos.commonEventManager (公共事件模块)

本模块提供了公共事件相关的能力，包括发布公共事件、订阅公共事件、以及退订公共事件。

> **说明：**
>
> 本模块首批接口从API version 9开始支持。后续版本的新增接口，采用上角标单独标记接口的起始版本。

## 导入模块

```ts
import { commonEventManager } from '@kit.BasicServicesKit';
```

## Support

系统公共事件是指由系统服务或系统应用发布的事件，订阅这些公共事件需要特定的权限、使用相应的值，详见[系统定义的公共事件](./common_event/commonEventManager-definitions.md)。

## commonEventManager.publish

publish(event: string, callback: AsyncCallback\<void>): void

发布公共事件。使用callback异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名     | 类型                 | 必填 | 说明                   |
| -------- | -------------------- | ---- | ---------------------- |
| event    | string               | 是   | 表示要发送的公共事件。详见[系统公共事件定义](./common_event/commonEventManager-definitions.md)。 |
| callback | AsyncCallback\<void> | 是   | 回调函数。当公共事件发布成功时，err为undefined，否则为错误对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)和[事件错误码](./errorcode-CommonEventService.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 1500003  | The common event sending frequency too high. |
| 1500007  | Failed to send the message to the common event service. |
| 1500008  | Failed to initialize the common event service. |
| 1500009  | Failed to obtain system parameters.  |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 发布公共事件
try {
  commonEventManager.publish('event', (err: BusinessError) => {
    if (err) {
      console.error(`Failed to publish common event. Code is ${err.code}, message is ${err.message}`);
      return;
    }
    console.info(`Succeeded in publishing common event.`);
  });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to publish common event. Code is ${err.code}, message is ${err.message}`);
}
```

## commonEventManager.publish

publish(event: string, options: CommonEventPublishData, callback: AsyncCallback\<void>): void

发布公共事件。使用callback异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名     | 类型                   | 必填 | 说明                   |
| -------- | ---------------------- | ---- | ---------------------- |
| event    | string                 | 是   | 表示要发布的公共事件。详见[系统公共事件定义](./common_event/commonEventManager-definitions.md)。  |
| options  | [CommonEventPublishData](./js-apis-inner-commonEvent-commonEventPublishData.md) | 是   | 表示发布公共事件的属性。 |
| callback | AsyncCallback\<void>   | 是   | 回调函数。当公共事件发布成功时，err为undefined，否则为错误对象。  |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)和[事件错误码](./errorcode-CommonEventService.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 1500003  | The common event sending frequency too high. |
| 1500007  | Failed to send the message to the common event service. |
| 1500008  | Failed to initialize the common event service. |
| 1500009  | Failed to obtain system parameters.  |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 公共事件相关信息，以发布有序公共事件为例
let options: commonEventManager.CommonEventPublishData = {
  code: 0,
  data: 'initial data',
  isOrdered: true // 有序公共事件
}

// 发布公共事件
try {
  commonEventManager.publish('event', options, (err: BusinessError) => {
    if (err) {
      console.error(`Failed to publish common event. Code is ${err.code}, message is ${err.message}`);
      return;
    }
    console.info(`Succeeded in publishing common event.`);
  });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to publish common event. Code is ${err.code}, message is ${err.message}`);
}
```

## commonEventManager.createSubscriber

createSubscriber(subscribeInfo: CommonEventSubscribeInfo, callback: AsyncCallback\<CommonEventSubscriber>): void

创建订阅者。使用callback异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名          | 类型                                                         | 必填 | 说明                       |
| ------------- | ------------------------------------------------------------ | ---- | -------------------------- |
| subscribeInfo | [CommonEventSubscribeInfo](./js-apis-inner-commonEvent-commonEventSubscribeInfo.md)        | 是   | 表示订阅信息。             |
| callback      | AsyncCallback\<[CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md)> | 是   | 回调函数。当公共事件订阅者创建成功时，err为undefined，否则为错误对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 401     | Parameter error. Possible causes:<br>1. Mandatory parameters are left unspecified.<br>2. Incorrect parameter types.<br>3. Parameter verification failed.    |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ['event']
};

// 创建订阅者
try {
  commonEventManager.createSubscriber(subscribeInfo,
    (err: BusinessError, commonEventSubscriber: commonEventManager.CommonEventSubscriber) => {
      if(!err) {
        console.info(`Succeeded in creating subscriber.`);
        subscriber = commonEventSubscriber;
        return;
      }
      console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
    });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
}
```

## commonEventManager.createSubscriber

createSubscriber(subscribeInfo: CommonEventSubscribeInfo): Promise\<CommonEventSubscriber>

创建订阅者。使用Promise异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名          | 类型                                                  | 必填 | 说明           |
| ------------- | ----------------------------------------------------- | ---- | -------------- |
| subscribeInfo | [CommonEventSubscribeInfo](./js-apis-inner-commonEvent-commonEventSubscribeInfo.md) | 是   | 表示订阅信息。 |

**返回值：**
| 类型                                                      | 说明             |
| --------------------------------------------------------- | ---------------- |
| Promise\<[CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md)> | 以Promise形式返回订阅者对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 401     | Parameter error. Possible causes:<br>1. Mandatory parameters are left unspecified.<br>2. Incorrect parameter types.<br>3. Parameter verification failed.      |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ['event']
};
// 创建订阅者
commonEventManager.createSubscriber(subscribeInfo).then((commonEventSubscriber: commonEventManager.CommonEventSubscriber) => {
  console.info(`Succeeded in creating subscriber.`);
  subscriber = commonEventSubscriber;
}).catch((err: BusinessError) => {
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
});
```

## commonEventManager.createSubscriberSync<sup>10+</sup>

createSubscriberSync(subscribeInfo: CommonEventSubscribeInfo): CommonEventSubscriber

createSubscriber的同步接口。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名          | 类型                                                  | 必填 | 说明           |
| ------------- | ----------------------------------------------------- | ---- | -------------- |
| subscribeInfo | [CommonEventSubscribeInfo](./js-apis-inner-commonEvent-commonEventSubscribeInfo.md) | 是   | 表示订阅信息。 |

**返回值：**
| 类型                                                      | 说明             |
| --------------------------------------------------------- | ---------------- |
| [CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md) | 返回订阅者对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 401     | Parameter error. Possible causes:<br>1. Mandatory parameters are left unspecified.<br>2. Incorrect parameter types.<br>3. Parameter verification failed.      |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ['event']
};
// 创建订阅者
try {
  subscriber = commonEventManager.createSubscriberSync(subscribeInfo);
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
}
```

## commonEventManager.subscribe

subscribe(subscriber: CommonEventSubscriber, callback: AsyncCallback\<CommonEventData>): void

订阅公共事件。使用callback异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名       | 类型                                                | 必填 | 说明                             |
| ---------- | ---------------------------------------------------- | ---- | -------------------------------- |
| subscriber | [CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md)     | 是   | 表示订阅者对象。                 |
| callback   | AsyncCallback\<[CommonEventData](./js-apis-inner-commonEvent-commonEventData.md)> | 是   | 回调函数。当公共事件订阅成功后，事件触发时执行的回调函数；否则订阅失败时，err为错误对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)和[事件错误码](./errorcode-CommonEventService.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 801  | capability not supported.               |
| 1500007  | Failed to send the message to the common event service. |
| 1500008  | Failed to initialize the common event service. |
| 1500010  | The count of subscriber exceed system specification. |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ['event']
};

// 创建订阅者
try {
  commonEventManager.createSubscriber(subscribeInfo,
    (err: BusinessError, commonEventSubscriber: commonEventManager.CommonEventSubscriber) => {
      if(!err) {
        console.info(`Succeeded in creating subscriber.`);
        subscriber = commonEventSubscriber;
        // 订阅公共事件
        try {
          commonEventManager.subscribe(subscriber, (err: BusinessError, data: commonEventManager.CommonEventData) => {
            if (err) {
              console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
              return;
            }
            console.info(`Succeeded in subscribing, data is ${JSON.stringify(data)}`);
          });
        } catch (error) {
          let err: BusinessError = error as BusinessError;
          console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
        }
        return;
      }
      console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
    });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
}
```

## commonEventManager.unsubscribe

unsubscribe(subscriber: CommonEventSubscriber, callback?: AsyncCallback\<void>): void

取消订阅公共事件。使用callback异步回调。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名       | 类型                                             | 必填 | 说明                     |
| ---------- | ----------------------------------------------- | ---- | ------------------------ |
| subscriber | [CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md) | 是   | 表示订阅者对象。         |
| callback   | AsyncCallback\<void>                            | 否   | 回调函数。当取消公共事件订阅成功时，err为undefined，否则为错误对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)和[事件错误码](./errorcode-CommonEventService.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 401     | Parameter error. Possible causes:<br>1. Mandatory parameters are left unspecified.<br>2. Incorrect parameter types.<br>3. Parameter verification failed.      |
| 801  | capability not supported.               |
| 1500007  | Failed to send the message to the common event service. |
| 1500008  | Failed to initialize the common event service. |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber | undefined;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ['event']
};

// 创建订阅者
try {
  commonEventManager.createSubscriber(subscribeInfo,
    (err: BusinessError, commonEventSubscriber: commonEventManager.CommonEventSubscriber) => {
      if(!err) {
        console.info(`Succeeded in creating subscriber.`);
        subscriber = commonEventSubscriber;
        // 订阅公共事件
        try {
          commonEventManager.subscribe(subscriber, (err: BusinessError, data: commonEventManager.CommonEventData) => {
            if (err) {
              console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
              return;
            }
            console.info(`Succeeded in subscribing, data is ${JSON.stringify(data)}`);
          });
        } catch (error) {
          let err: BusinessError = error as BusinessError;
          console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
        }
        return;
      }
      console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
    });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
}

// 取消订阅公共事件
// 等待异步接口subscribe执行完毕，开发者根据实际业务选择是否需要添加setTimeout
setTimeout(() => {
  try {
    commonEventManager.unsubscribe(subscriber, (err: BusinessError) => {
      if (err) {
        console.error(`Failed to unsubscribe. Code is ${err.code}, message is ${err.message}`);
        return;
      }
      // subscriber不再使用时需要将其置为undefined，避免内存泄露
      subscriber = undefined;
      console.info(`Succeeded in unsubscribing.`);
    });
  } catch (error) {
    let err: BusinessError = error as BusinessError;
    console.error(`Failed to unsubscribe. Code is ${err.code}, message is ${err.message}`);
  }
}, 500);
```

## commonEventManager.subscribeToEvent<sup>20+</sup>

subscribeToEvent(subscriber: CommonEventSubscriber, callback: Callback\<CommonEventData>): Promise\<void>

订阅公共事件，并返回订阅成功或失败信息。使用Promise异步回调。

**原子化服务API：** 从API version 20开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

**参数：**

| 参数名       | 类型                                                | 必填 | 说明                             |
| ---------- | ---------------------------------------------------- | ---- | -------------------------------- |
| subscriber | [CommonEventSubscriber](./js-apis-inner-commonEvent-commonEventSubscriber.md)     | 是   | 表示订阅者对象。                 |
| callback   | Callback\<[CommonEventData](./js-apis-inner-commonEvent-commonEventData.md)> | 是   | 表示接收公共事件数据的回调函数。 |

**返回值：**
| 类型                                                      | 说明             |
| --------------------------------------------------------- | ---------------- |
| Promise\<void>   | Promise对象。无返回结果的Promise对象。 |

**错误码：**

以下错误码的详细介绍请参见[通用错误码](../errorcode-universal.md)和[事件错误码](./errorcode-CommonEventService.md)。

| 错误码ID | 错误信息                            |
| -------- | ----------------------------------- |
| 801  | Capability not supported.               |
| 1500007  | Failed to send the message to the common event service. |
| 1500008  | Failed to initialize the common event service. |
| 1500010  | The count of subscriber exceed system specification. |

**示例：**

```ts
import { BusinessError } from '@kit.BasicServicesKit';

// 定义订阅者，用于保存创建成功的订阅者对象，后续使用其完成订阅及退订的动作
let subscriber: commonEventManager.CommonEventSubscriber;
// 订阅者信息
let subscribeInfo: commonEventManager.CommonEventSubscribeInfo = {
  events: ["event"]
};

// 创建订阅者
try {
  commonEventManager.createSubscriber(subscribeInfo,
    (err: BusinessError, commonEventSubscriber: commonEventManager.CommonEventSubscriber) => {
      if (err) {
        console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
      } else {
        console.info(`Succeeded in creating subscriber.`);
        subscriber = commonEventSubscriber;
        // 订阅公共事件
        try {
          commonEventManager.subscribeToEvent(subscriber, (data: commonEventManager.CommonEventData) => {
            console.info(`Succeeded to receive common event, data is ` + JSON.stringify(data));
          }).then(() => {
            console.info(`Succeeded to subscribe.`);
          }).catch((err: BusinessError) => {
            console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
          });
        } catch (error) {
          let err: BusinessError = error as BusinessError;
          console.error(`Failed to subscribe. Code is ${err.code}, message is ${err.message}`);
        }
      }
    });
} catch (error) {
  let err: BusinessError = error as BusinessError;
  console.error(`Failed to create subscriber. Code is ${err.code}, message is ${err.message}`);
}
```

## CommonEventData<sup>10+</sup>

type CommonEventData = _CommonEventData

表示公共事件的数据。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

| 类型 | 说明 |
| --- | --- |
| [_CommonEventData](js-apis-inner-commonEvent-commonEventData.md) | 表示公共事件的数据。 |

## CommonEventSubscriber<sup>10+</sup>

type CommonEventSubscriber = _CommonEventSubscriber

描述公共事件的订阅者。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

| 类型 | 说明 |
| --- | --- |
| [_CommonEventSubscriber](js-apis-inner-commonEvent-commonEventSubscriber.md) | 描述公共事件的订阅者。 |

## CommonEventSubscribeInfo<sup>10+</sup>

type CommonEventSubscribeInfo = _CommonEventSubscribeInfo

用于表示订阅者的信息。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

| 类型 | 说明 |
| --- | --- |
| [_CommonEventSubscribeInfo](js-apis-inner-commonEvent-commonEventSubscribeInfo.md) | 用于表示订阅者的信息。 |

## CommonEventPublishData<sup>10+</sup>

type CommonEventPublishData = _CommonEventPublishData

描述公共事件内容和属性。

**原子化服务API：** 从API version 11开始，该接口支持在原子化服务中使用。

**系统能力：** SystemCapability.Notification.CommonEvent

| 类型 | 说明 |
| --- | --- |
| [_CommonEventPublishData](js-apis-inner-commonEvent-commonEventPublishData.md) | 描述公共事件内容和属性。 |