鸿蒙应用开发 FA模型：DataAbility组件（三）

sy7748

501人浏览 · 2025-06-25 20:50:00

sy7748 · 2025-06-25 20:50:00 发布

访问DataAbility

访问DataAbility需导入基础依赖包，以及获取与DataAbility子模块通信的URI字符串。

其中，基础依赖包包括：

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

访问DataAbility的示例代码如下：

1. 创建工具接口类对象。

import featureAbility from '@ohos.ability.featureAbility';
import ohos_data_ability from '@ohos.data.dataAbility';
import ability from '@ohos.ability.ability';
// 作为参数传递的URI,与config中定义的URI的区别是多了一个"/",有三个"/"
let uri: string = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
let DAHelper: ability.DataAbilityHelper = featureAbility.acquireDataAbilityHelper(uri);

2. 构建数据库相关的RDB数据。

import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
let valuesBucket_insert: rdb.ValuesBucket = { name: 'Rose', introduction: 'insert' };
let valuesBucket_update: rdb.ValuesBucket = { name: 'Rose', introduction: 'update' };
let crowd = new Array({ name: 'Rose', introduction: 'batchInsert_one' } as rdb.ValuesBucket,
  { name: 'Rose', introduction: 'batchInsert_two' } as rdb.ValuesBucket);
let columnArray = new Array('id', 'name', 'introduction');
let predicates = new ohos_data_ability.DataAbilityPredicates();

注：关于DataAbilityPredicates的详细内容，请参考DataAbility谓词。

3. 调用insert方法向指定的DataAbility子模块插入数据。

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';

// callback方式调用:
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private valuesBucket_insert: rdb.ValuesBucket = { name: 'Rose', introduction: 'insert' };
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // callback方式调用:
              this.DAHelper.insert(this.uri, this.valuesBucket_insert, (error: BusinessError, data: number) => {
                if (error && error.code !== 0) {
                  promptAction.showToast({
                    message: 'insert_failed_toast'
                  });
                } else {
                  promptAction.showToast({
                    message: 'insert_success_toast'
                  });
                }
                hilog.info(domain, TAG, 'DAHelper insert result: ' + data + ', error: ' + JSON.stringify(error));
              }
              );
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private valuesBucket_insert: rdb.ValuesBucket = { name: 'Rose', introduction: 'insert' };
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              this.DAHelper.insert(this.uri, this.valuesBucket_insert).then((datainsert) => {
                promptAction.showToast({
                  message: 'insert_success_toast'
                });
                hilog.info(domain, TAG, 'DAHelper insert result: ' + datainsert);
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'insert_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper insert failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

4. 调用delete方法删除DataAbility子模块中指定的数据。

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // callback方式调用:
              this.DAHelper.delete(this.uri, this.predicates, (error, data) => {
                if (error && error.code !== 0) {
                  promptAction.showToast({
                    message: 'delete_failed_toast'
                  });
                } else {
                  promptAction.showToast({
                    message: 'delete_success_toast'
                  });
                }
                hilog.info(domain, TAG, 'DAHelper delete result: ' + data + ', error: ' + JSON.stringify(error));
              }
              );
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              this.DAHelper.delete(this.uri, this.predicates).then((datadelete) => {
                promptAction.showToast({
                  message: 'delete_success_toast'
                });
                hilog.info(domain, TAG, 'DAHelper delete result: ' + datadelete);
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'delete_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper delete failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

5. 调用update方法更新指定DataAbility子模块中的数据。

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private valuesBucket_update: rdb.ValuesBucket = { name: 'Rose', introduction: 'update' };
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // callback方式调用:
              this.predicates.equalTo('name', 'Rose');
              this.DAHelper.update(this.uri, this.valuesBucket_update, this.predicates, (error, data) => {
                if (error && error.code !== 0) {
                  promptAction.showToast({
                    message: 'update_failed_toast'
                  });
                } else {
                  promptAction.showToast({
                    message: 'update_success_toast'
                  });
                }
                hilog.info(domain, TAG, 'DAHelper update result: ' + data + ', error: ' + JSON.stringify(error));
              }
              );
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private valuesBucket_update: rdb.ValuesBucket = { name: 'Rose', introduction: 'update' };
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              this.predicates.equalTo('name', 'Rose');
              this.DAHelper.update(this.uri, this.valuesBucket_update, this.predicates).then((dataupdate) => {
                promptAction.showToast({
                  message: 'update_success_toast'
                });
                hilog.info(domain, TAG, 'DAHelper update result: ' + dataupdate);
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'update_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper update failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

6. 调用query方法在指定的DataAbility子模块中查找数据。

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private columnArray = new Array('id', 'name', 'introduction');
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // callback方式调用:
              this.predicates.equalTo('name', 'Rose');
              this.DAHelper.query(this.uri, this.columnArray, this.predicates, (error, data) => {
                if (error && error.code !== 0) {
                  promptAction.showToast({
                    message: 'query_failed_toast'
                  });
                  hilog.error(domain, TAG, `DAHelper query failed. Cause: ${error.message}`);
                } else {
                  promptAction.showToast({
                    message: 'query_success_toast'
                  });
                }
                // ResultSet是一个数据集合的游标，默认指向第-1个记录，有效的数据从0开始。
                while (data.goToNextRow()) {
                  const id = data.getLong(data.getColumnIndex('id'));
                  const name = data.getString(data.getColumnIndex('name'));
                  const introduction = data.getString(data.getColumnIndex('introduction'));
                  hilog.info(domain, TAG, `DAHelper query result:id = [${id}], name = [${name}], introduction = [${introduction}]`);
                }
                // 释放数据集的内存
                data.close();
              }
              );
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private columnArray = new Array('id', 'name', 'introduction');
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              this.predicates.equalTo('name', 'Rose');
              this.DAHelper.query(this.uri, this.columnArray, this.predicates).then((dataquery) => {
                promptAction.showToast({
                  message: 'query_success_toast'
                });
                // ResultSet是一个数据集合的游标，默认指向第-1个记录，有效的数据从0开始。
                while (dataquery.goToNextRow()) {
                  const id = dataquery.getLong(dataquery.getColumnIndex('id'));
                  const name = dataquery.getString(dataquery.getColumnIndex('name'));
                  const introduction = dataquery.getString(dataquery.getColumnIndex('introduction'));
                  hilog.info(domain, TAG, `DAHelper query result:id = [${id}], name = [${name}], introduction = [${introduction}]`);
                }
                // 释放数据集的内存
                dataquery.close();
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'query_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper query failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

7. 调用batchInsert方法向指定的DataAbility子模块批量插入数据。

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private crowd = new Array({ name: 'Rose', introduction: 'batchInsert_one' } as rdb.ValuesBucket,
    { name: 'Rose', introduction: 'batchInsert_two' } as rdb.ValuesBucket);
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // callback方式调用:
              this.DAHelper.batchInsert(this.uri, this.crowd, (error, data) => {
                if (error && error.code !== 0) {
                  promptAction.showToast({
                    message: 'batchInsert_failed_toast'
                  });
                } else {
                  promptAction.showToast({
                    message: 'batchInsert_success_toast'
                  });
                }
                hilog.info(domain, TAG, 'DAHelper batchInsert result: ' + data + ', error: ' + JSON.stringify(error));
              }
              );
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private crowd = new Array({ name: 'Rose', introduction: 'batchInsert_one' } as rdb.ValuesBucket,
    { name: 'Rose', introduction: 'batchInsert_two' } as rdb.ValuesBucket);
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              this.DAHelper.batchInsert(this.uri, this.crowd).then((databatchInsert) => {
                promptAction.showToast({
                  message: 'batchInsert_success_toast'
                });
                hilog.info(domain, TAG, 'DAHelper batchInsert result: ' + databatchInsert);
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'batchInsert_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper batchInsert failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

8. 调用executeBatch方法向指定的DataAbility子模块进行数据的批量处理。

    <pre class="ts prettyprint linenums hljs language-typescript" data-highlighted="yes" style="box-sizing: border-box; margin: 12px 0px 5px; padding: 8px 0px 0px; font-family: HarmonyOSHans-Regular, monospace, HarmonyOSHans-fallback, PingFangSC-Regular, &quot;Microsoft YaHei&quot;, Arial, Helvetica, sans-serif; vertical-align: baseline; border: 0px; font-size: 14px; overflow: visible; line-height: 1.45; overflow-wrap: break-word; white-space: pre-wrap; background-color: rgb(241, 243, 244); border-radius: 16px; position: relative;">

    1.  import ability from '@ohos.ability.ability';
    2.  import featureAbility from '@ohos.ability.featureAbility';
    3.  import { BusinessError } from '

import ability from '@ohos.ability.ability';
import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';
import ohos_data_ability from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import promptAction from '@ohos.promptAction';
import hilog from '@ohos.hilog';

const TAG: string = 'PageDataAbility';
const domain: number = 0xFF00;

@Entry
@Component
struct PageDataAbility {
  private predicates = new ohos_data_ability.DataAbilityPredicates();
  private uri = 'dataability:///com.samples.famodelabilitydevelop.DataAbility';
  private DAHelper = featureAbility.acquireDataAbilityHelper(this.uri);

  build() {
    Column() {
      // ...
      List({ initialIndex: 0 }) {
        // ...
        ListItemGroup() {
          ListItem() {
            Flex({ justifyContent: FlexAlign.SpaceBetween, alignContent: FlexAlign.Center }) {
              // ...
            }
            .onClick(() => {
              // promise方式调用(await需要在async方法中使用):
              let operations: Array<ability.DataAbilityOperation> = [{
                uri: this.uri,
                type: featureAbility.DataAbilityOperationType.TYPE_INSERT,
                valuesBucket: { name: 'Rose', introduction: 'executeBatch' },
                predicates: this.predicates,
                expectedCount: 0,
                predicatesBackReferences: undefined,
                interrupted: true,
              }];
              this.DAHelper.executeBatch(this.uri, operations).then((dataquery) => {
                promptAction.showToast({
                  message: 'executeBatch_success_toast'
                });
                hilog.info(domain, TAG, 'DAHelper executeBatch result: ' + JSON.stringify(dataquery));
              }).catch((error: BusinessError) => {
                promptAction.showToast({
                  message: 'executeBatch_failed_toast'
                });
                hilog.error(domain, TAG, `DAHelper executeBatch failed. Cause: ${error.message}`);
              });
            })
          }
          // ...
        }
        // ...
      }
      // ...
    }
    // ...
  }
}

DataAbility的客户端的接口是由工具接口类对象DataAbilityHelper向外提供，相关接口可参考 DataAbilityHelper模块 )。

DataAbility权限控制

DataAbility提供数据服务，并不是所有的Ability都有权限读写它，DataAbility有一套权限控制机制来保证数据安全。分为静态权限控制和动态权限控制两部分。

静态权限控制

DataAbility作为服务端，在被拉起的时候，会根据config.json里面配置的权限来进行校验，有"readPermission"、"writePermission"和"Permission"三个配置项，可以不配或者为空。示例如下:

"abilities": [
  ...
  {
    "name": ".DataAbility",
    "srcLanguage": "ets",
    "srcPath": "DataAbility",
    "icon": "$media:icon",
    "description": "$string:DataAbility_desc",
    "type": "data",
    "visible": true,
    "uri": "dataability://com.samples.famodelabilitydevelop.DataAbility",
    "readPermission": "ohos.permission.READ_CONTACTS",
    "writePermission": "ohos.permission.WRITE_CONTACTS"
  },
  ...
]

客户端在拉起DataAbility的时候，需要校验客户端是否有权限拉起该DataAbility。客户端的权限配置在config.json配置文件的"module"对象的"reqPermissions"对象中，示例如下：

{
  ...
  "module": {
    ...
    "reqPermissions": [
      {
        "name": "ohos.permission.READ_CONTACTS"
      },
      {
        "name": "ohos.permission.WRITE_CONTACTS"
      },
      ...
    ],
    ...
  }
}

动态权限控制

静态权限校验只能控制某个DataAbility是否能被另一个Ability或应用拉起，无法精确校验每个读写接口的权限，因为拉起DataAbility的时候，还不知道应用是否需要读写它的数据。

动态权限控制是校验每个数据操作的接口是否有对应的权限。客户端调用数据操作接口所需的权限如下表所示。

表1 接口对应的读写权限配置

需要配置读权限的接口	需要配置写权限的接口	据实际操作配置读写权限的接口
query、normalizeUri、denormalizeUri、openfile（传入mode有’r’）	insert、batchInsert、delete、update、openfile（传入mode有’w’）	executeBatch

对于需要配置读权限的接口，服务端需要配置readPermission，客户端必须申请相应的读权限才能调用相关的接口。

对于需要配置写权限的接口，服务端需要配置writePermission，客户端必须申请相应的写权限才能调用相关的接口。

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