harmony 鸿蒙Accessing a DataAbility

2023-02-03
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Accessing a DataAbility

To access a DataAbility, import the basic dependency packages and obtain the URI string for communicating with the DataAbility.

The basic dependency packages include:

@ohos.ability.featureAbility
@ohos.data.dataAbility
@ohos.data.relationalStore

The sample code for accessing a DataAbility is as follows:

Create a DataAbilityHelper instance.

   // Different from the URI defined in the config.json file, the URI passed in the parameter has an extra slash (/), three slashes in total.
   import featureAbility from '@ohos.ability.featureAbility'
   import ohos_data_ability from '@ohos.data.dataAbility'
   import relationalStore from '@ohos.data.relationalStore'
   
   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);

Construct RDB data.

   import ohos_data_ability from '@ohos.data.dataAbility'
   import rdb from '@ohos.data.rdb'

   let valuesBucket: rdb.ValuesBucket = {"name": "gaolu"}
   let da = new ohos_data_ability.DataAbilityPredicates()
   let valArray = new Array("value1");
   let cars = new Array({"batchInsert1" : "value1",} as rdb.ValuesBucket);

For details about DataAbilityPredicates, see DataAbility Predicates.

Use insert to insert data to the DataAbility.

   import { BusinessError } from '@ohos.base';

   // Callback mode:
   DAHelper.insert(
     urivar,
     valuesBucket,
     (error: BusinessError, data: number) => {
       console.info("DAHelper insert result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'
   import { BusinessError } from '@ohos.base';

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let datainsert = await DAHelper.insert(urivar, valuesBucket).then((data) => {
     console.info("insert success.");
   }).catch((error: BusinessError) => {
     console.error("insert failed.");
   });

Use delete to delete data from the DataAbility.

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Callback mode:
   DAHelper.delete(
     urivar,
     da,
     (error, data) => {
       console.info("DAHelper delete result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let datadelete = await DAHelper.delete(
     urivar,
     da,
   );

Use update to update data in the DataAbility.

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Callback mode:
   DAHelper.update(
     urivar,
     valuesBucket,
     da,
     (error, data) => {
       console.info("DAHelper update result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let dataupdate = await DAHelper.update(
     urivar,
     valuesBucket,
     da,
   );

Use query to query data in the DataAbility.

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Callback mode:
   DAHelper.query(
     urivar,
     valArray,
     da,
     (error, data) => {
       console.info("DAHelper query result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let dataquery = await DAHelper.query(
     urivar,
     valArray,
     da
   );

Use batchInsert to insert data in batches to the DataAbility.

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Callback mode:
   DAHelper.batchInsert(
     urivar,
     cars,
     (error, data) => {
       console.info("DAHelper batchInsert result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let databatchInsert = await DAHelper.batchInsert(
     urivar,
     cars
   );

Use executeBatch to process data in batches in the DataAbility.

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Callback mode:
   DAHelper.executeBatch(
     urivar,
     [
       {
         uri: urivar,
         type: featureAbility.DataAbilityOperationType.TYPE_INSERT,
         valuesBucket: {"executeBatch" : "value1",},
         predicates: da,
         expectedCount:0,
         predicatesBackReferences: undefined,
         interrupted:true,
       }
     ],
     (error, data) => {
       console.info("DAHelper executeBatch result: " + data)
     }
   );

   import featureAbility from '@ohos.ability.featureAbility'

   let urivar = "dataability:///com.ix.DataAbility"
   let DAHelper = featureAbility.acquireDataAbilityHelper(urivar);
   // Promise mode (await needs to be used in the asynchronous method):
   let dataexecuteBatch = await DAHelper.executeBatch(
     urivar,
     [
       {
         uri: urivar,
         type: featureAbility.DataAbilityOperationType.TYPE_INSERT,
         valuesBucket:
         {
           "executeBatch" : "value1",
         },
         predicates: da,
         expectedCount:0,
         predicatesBackReferences: undefined,
         interrupted:true,
       }
     ]
   );

The APIs for operating a DataAbility are provided by DataAbilityHelper. For details about the APIs, see DataAbilityHelper.