关于indexedDB的基本使用

window.indexedDB = window.indexedDB || window.webkitIndexedDB || window.mozIndexedDB || window.msIndexedDB;    window.IDBTransaction = window.IDBTransaction || window.webkitIDBTransaction || window.msIDBTransaction;    window.IDBKeyRange = window.IDBKeyRange || window.webkitIDBKeyRange || window.msIDBKeyRange;    window.IDBCursor = window.IDBCursor || window.webkitIDBCursor || window.msIDBCursor;    //连接数据库    function connectDatabase() {        var dbName = "indexedDBTest";        var dbVersion = 20170633        var idb;        var dbConnect = indexedDB.open(dbName, dbVersion);        //连接成功        dbConnect.onsuccess = function(e) {            idb = e.target.result;            console.log(e);            console.log("连接成功");            //开启事物            var tx = idb.transaction(["newUsers"], "readwrite");            var store = tx.objectStore("newUsers");            var value = {                userId: 1,                userName: "李四",                address: "广东省"            };            var req = store.put(value);            req.onsuccess = function(e) {                console.log("保存成功");            };            req.onerror = function(e) {                console.log("保存失败");            }        };        dbConnect.onerror = function() {            console.log("连接失败");        };        //数据库更新        dbConnect.onupgradeneeded = function(e) {            idb = e.target.result;            var tx = e.target.transaction;            var oldVersion = e.oldVersion;            var newVersion = e.newVersion;            console.log("数据库已经更新");            //添加数据            var name = "newUsers";            var optionalParameters = {                keyPath: "userId", //表示主键                autoIncrement: true //主键是否自动增长            };            //createObjectStore(仓库名称,对象)            var store = idb.createObjectStore(name, optionalParameters);            //创建唯一索引            var name = "userNameIndex";            var keyPath = "userName";            var optionalParameters = {                unique: false,                multiEntry: false            };            //创建唯一索引            var idx = store.createIndex(name, keyPath, optionalParameters);        };    }