indexdb增删改查基本使用如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0">
<title>Title</title>
<link href="./favicon.png">
</head>
<body>
</body>
<script>
let dbName = 'helloIndexDB', version = 1, storeName = 'helloStore'
//打开创建数据库
let indexedDB = window.indexedDB
let db
const request = indexedDB.open(dbName, version)
request.onsuccess = function(event) {
db = event.target.result // 数据库对象
console.log('数据库打开成功')
}
request.onerror = function(event) {
console.log('数据库打开报错')
}
request.onupgradeneeded = function(event) {
// 数据库创建或升级的时候会触发
console.log('onupgradeneeded')
db = event.target.result // 数据库对象
let objectStore
if (!db.objectStoreNames.contains(storeName)) {
// 创建表
console.log("创建数据库表")
objectStore = db.createObjectStore(storeName, { keyPath: 'id' })
// objectStore.createIndex('name', 'name', { unique: true }) // 创建索引 可以让你搜索任意字段
}
}
// 添加数据
function addData(db, storeName, data) {
let request = db.transaction([storeName], 'readwrite') // 事务对象 指定表格名称和操作模式（"只读"或"读写"）
.objectStore(storeName) // 仓库对象
.add(data)
request.onsuccess = function(event) {
console.log('数据写入成功',event)
}
request.onerror = function(event) {
console.log('数据写入失败')
throw new Error(event.target.error)
}
}
// 根据id获取数据
function getDataByKey(db, storeName, key) {
let transaction = db.transaction([storeName]) // 事务
let objectStore = transaction.objectStore(storeName) // 仓库对象
let request = objectStore.get(key)
request.onerror = function(event) {
console.log('事务失败')
}
request.onsuccess = function(event) {
console.log('主键查询结果: ', request.result)
}
}
// 根据id修改数据
function updateDB(db, storeName, data) {
let request = db.transaction([storeName], 'readwrite') // 事务对象
.objectStore(storeName) // 仓库对象
.put(data)
request.onsuccess = function() {
console.log('数据更新成功')
}
request.onerror = function() {
console.log('数据更新失败')
}
}
// 根据id删除数据
function deleteDB(db, storeName, id) {
let request = db.transaction([storeName], 'readwrite').objectStore(storeName).delete(id)
request.onsuccess = function() {
console.log('数据删除成功')
}
request.onerror = function() {
console.log('数据删除失败')
}
}
// 由于打开indexDB是异步的加个定时器避免 db对象还没获取到值导致 报错
setTimeout(() => {
addData(db, storeName, {
id: new Date().getTime(), // 必须且值唯一
name: '张三',
age: 18,
desc: 'helloWord'
})
getDataByKey(db, storeName, 1691391929283)//1691391929283插入数据ID
updateDB(db, storeName, {id: 1691391929283, desc: '修改的内容1'})
getDataByKey(db, storeName, 1691391929283)
deleteDB(db, storeName, 1691391929283)
getDataByKey(db, storeName, 1691391929283)
}, 1000)
</script>
</html>
运行之后：
控制台查看IndexDb缓存，也可以查看到对应数据
