1.indexedDB数据库时一种事务类型数据库
2.是NoSQL数据库
3.使用JS对象存储数据
创建数据库
1.indexedDB.open创建数据库
2.open方法返回一个IDBRequest对象
<script>
var db = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
var request, result, version = 2,
dbName = 'testDB',
osName = 'objectStore';
function createDB() {
request = db.open(dbName, version)
//请求有三种状态,如下:
request.onsuccess = function() { // 打开数据库成功
db = request.result;
console.log('open success');
}
request.onerror = function(e) { // 打开数据库失败
console.log(e.currentTarget.errormessage)
}
request.onupgradeneeded = function(e) { //请求数据库版本变化时
db = request.result;
console.log('upgradeneeded ');
}
}
createDB()
<script>
如何创建“表”(ObjectStore)
1.indexedDB.createObjectStore创建ObjectStore
2.createObjectStore 方法可以设置主键类型
<script>
var db = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
var request, result, version = 2,
dbName = 'testDB',
osName = 'os1';
function createDB() {
request = db.open(dbName, version)
//请求有三种状态,如下:
request.onsuccess = function() { // 打开数据库成功
db = request.result;
console.log('open success');
}
request.onerror = function(e) { // 打开数据库失败
console.log(e.currentTarget.errormessage)
}
request.onupgradeneeded = function(e) { //请求数据库版本变化时
db = request.result;
if (!db.objectStoreNames.contains(osName)) {
db.createObjectStore(osName, {autoIncrement: true}) // 创建的表的主建是自增型的
}
}
}
createDB()
<script>