在chrome(版本 70.0.3538.110)测试正常
编写涉及:css, html, js
html代码
<h1>indexedDB</h1> <h2>在 DevTools 的 Application 中查看数据库信息</h2> <button onclick="addDBData()">添加数据</button> <div> <button onclick="getDBData()">获取数据</button> <input type="text" id="getID" placeholder="请输入ID"> </div> <div> <button onclick="delDBData()">删除数据</button> <input type="text" id="delID" placeholder="请输入ID"> </div> <div> <button onclick="updateDBData()">更新数据</button> <input type="text" id="updateID" placeholder="请输入ID"> </div> <div id="display"></div>
css代码
button { margin: 10px 0; padding: 8px 10px; border: 0; color: #fff; background-color: rgb(7, 196, 230); } input{ padding: 8px 5px; border: rgb(7, 196, 230) solid 1px }
JavaScript代码
window.indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB; if (!window.indexedDB) { alert('不支持indexDB') } const DATA_BASE = 'TEST_DB' let db = {} /** 1. 不存在当前数据库时,即为创建 2. open参数:数据库名称,版本号(整数) */ const request = window.indexedDB.open(DATA_BASE, 1) request.onerror = function (e) { console.error('error', e) } /** 1. 数据库已存在,打开成功 */ request.onsuccess = function (event) { db = event.target.result console.log('execute onsuccess'); }; /** 1. 当数据库不存在时,创建数据库会触发 onupgradeneeded 事件 2. 当指定的版本号高于当前时会直接触发 onupgradeneeded 事件 3. 唯一可以修改数据库结构的事件 */ request.onupgradeneeded = function (event) { /** 1. 保存 IDBDataBase 接口(数据库) */ db = event.target.result console.log('execute onupgradeneeded'); /** 1.使用键生成器,测试时,去除注释即可 */ // const objectStore = db.createObjectStore('users', { autoIncrement : true }) // objectStore.add({name: '123'}); // objectStore.add('123'); /** 1. 为当前数据库创建对象仓库(表) 2. 这里的keyPath 相当于主键 3. createIndex(indexName, keyPath, {unique | multiEntry | locale}) */ const objectStore = db.createObjectStore('users', { keyPath: 'id' }) objectStore.createIndex('name', 'name', { unique: false }) objectStore.createIndex('age', 'age', { unique: false }) /** 1. 确保初始化数据的时候,对象仓库已经创建完毕 */ objectStore.transaction.oncomplete = function(event) { const transaction = db.transaction(['users'], 'readwrite') const objStore = transaction.objectStore('users') objStore.add({ id: 12, name: `hew-${Math.random()}` , age: parseInt( Math.random() * 100, 10) }) } } /** 1. 所有数据库操作都基于事务 2. 事务三种模式:readonly,readwrite,versionchange 3. 修改数据库模式或结构——包括新建或删除对象仓库或索引,只能用 versionchange 模式 */ function addDBData() { const transaction = db.transaction(['users'], 'readwrite') const objectStore = transaction.objectStore('users') const request = objectStore.add({ id: Math.random() * 10, name: `hew-${Math.random()}` , age: parseInt( Math.random() * 100, 10) }) transaction.oncomplete = function (event) { console.log('transaction add complete') } transaction.onerror = function (error) { console.error('add error', error) } request.onsuccess = function (event) { console.log('add complete') } } function getDBData() { const id = parseFloat(document.getElementById('getID').value) const transaction = db.transaction(['users'], 'readwrite') const objectStore = transaction.objectStore('users') /** 1. 注意数据类型 */ const request = objectStore.get(id) request.onsuccess = function (event) { console.log('get complete', event.target.result) document.getElementById('display').innerHTML = JSON.stringify(request.result) } request.onerror = function (err) { console.error('get error', err) } } function updateDBData() { const id = parseFloat(document.getElementById('updateID').value) const transaction = db.transaction(['users'], 'readwrite') const objectStore = transaction.objectStore('users') const request = objectStore.get(id) request.onsuccess = function (event) { const d = event.target.result d.name = 'name name' const objectStoreUpdate = objectStore.put(d) objectStoreUpdate.onsuccess = function (e) { console.log('update success') } document.getElementById('display').innerHTML = 'update success' } request.onerror = function (err) { console.error('get error', err) } } function delDBData() { const id = parseFloat(document.getElementById('delID').value) const request = db.transaction(['users'], 'readwrite').objectStore('users').delete(id) request.onsuccess = function() { console.log('delete complete', id); } }
若有疑问或错误,请留言,谢谢!Github blog issues
来源:https://www.cnblogs.com/he-wei/p/10062580.html