鸿蒙jsapi操作数据库
时间: 2024-05-10 20:16:01 浏览: 12
鸿蒙操作数据库可以使用ohos.data.DatabaseHelper类,这个类提供了操作数据库的一些方法,包括创建数据库、表、插入、更新、删除、查询等。
首先,需要在manifest.json文件中声明数据库的权限:
```json
"ohos": {
"ability": [
{
"name": "com.example.myapp.MyAbility",
"label": "My Ability",
"description": "My Ability",
"type": "page",
"uri": "/MainAbility",
"actions": [
{
"name": "action1",
"entities": [
"entity1"
]
}
],
"permissions": [
"ohos.permission.DISTRIBUTED_DATASYNC",
"ohos.permission.DATABASE"
]
}
]
}
```
然后,在代码中可以使用以下步骤操作数据库:
1. 创建DatabaseHelper对象
```javascript
import ohos.data.DatabaseHelper;
const databaseHelper = new DatabaseHelper(context);
```
2. 创建数据库
```javascript
const db = databaseHelper.getReadableDatabase();
```
3. 创建表
```javascript
const CREATE_TABLE_SQL = 'CREATE TABLE IF NOT EXISTS user (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, age INTEGER)';
db.execSQL(CREATE_TABLE_SQL);
```
4. 插入数据
```javascript
const INSERT_SQL = 'INSERT INTO user (name, age) VALUES (?, ?)';
db.execSQL(INSERT_SQL, ['张三', 20]);
```
5. 更新数据
```javascript
const UPDATE_SQL = 'UPDATE user SET age = ? WHERE name = ?';
db.execSQL(UPDATE_SQL, [25, '张三']);
```
6. 删除数据
```javascript
const DELETE_SQL = 'DELETE FROM user WHERE name = ?';
db.execSQL(DELETE_SQL, ['张三']);
```
7. 查询数据
```javascript
const SELECT_SQL = 'SELECT * FROM user WHERE name = ?';
const cursor = db.rawQuery(SELECT_SQL, ['张三']);
if (cursor !== null) {
while (cursor.moveToNext()) {
const id = cursor.getInt(cursor.getColumnIndex('id'));
const name = cursor.getString(cursor.getColumnIndex('name'));
const age = cursor.getInt(cursor.getColumnIndex('age'));
console.info(`id: ${id}, name: ${name}, age: ${age}`);
}
cursor.close();
}
```
以上就是鸿蒙操作数据库的基本步骤,具体可以根据实际需要进行调整。
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