IndexDB代码 功能

<!doctype html>

<html lang="en">

<head>

    <meta charset="utf-8">

    <title>Learn IndexedDB</title>   

</head>

<body>

   

    <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*

            var store = null;

            db = e.target.result;

            console.log('upgradeneeded');

            if (!db.objectStoreNames.contains(osName)) {

                *// db.createObjectStore(osName, {autoIncrement: true}) // 创建的表的主建是自增型的*

                store = db.createObjectStore(osName, { keyPath: 'id' }) *// 创建的表以字段为主建*

                store.createIndex('idIndex', 'id', { unique: true }); *//创建索引字段id唯一*

                store.createIndex('categoryIndex', 'category', { multiEntry: true }); *//创建索引字段为数组*

                store.createIndex('hpIndex', 'hp', { unique: false });

            }            

           

        }

    }

    createDB()

    *// save data*

    var data = [{

        name: '史莱姆',

        id: '001',

        hp: 3,

        category: ['怪物', '容易逃跑']

    }, {

        name: '小蝙蝠',

        id: '002',

        hp: 5,

        category: ['怪物', '飞行']

    }, {

        name: '小恶魔',

        id: '003',

        hp: 9,

        category: ['怪物', '恶魔']

    }]

    *// use IDBObjectStore.add to save data*

    console.log(db);

    function addData() {

        if (!db) { alert("db"); }

        var transaction, store;

        transaction = db.transaction(osName, 'readwrite'); *//打开一个事务，读写模式*

        store = transaction.objectStore(osName) *///获取osName指定的 object store*

        data.map(function(*o*) {

            store.add(o)

            *// request = store.add(o) //增加数据*

            *//   if (data.length - 1 === i) {*

            *//     request.onsuccess = function () {*

            *//       console.log('alreay add all data to db')*

            *//       showCurrentData()*

            *//     }*

            *//   }*

        })

    }

    function getData(*id*) {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName);

        var request = store.get(id);

        request.onsuccess = function() {

            console.log(request.result);

        }

    }

    function getAllData() {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName);

        var request = store.getAll();

        request.onsuccess = function() {

            console.log(request.result);

        }

    }

    function updateData(*id*) {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName);

        var request = store.get(id);

        request.onsuccess = function() {

            request = store.put({ *//更新即可以更新也可以添加，取决于关键字是否有重复*

                name: '小花猫',

                id: id,

                hp: 9

            });

        }

    }

    function deleteData(*id*) {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName);

        var request = store.delete(id);

        request.onsuccess = function() {

            console.log('delete success');

        }

    }

    function clear() {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName);

        var request = store.clear();

        request.onsuccess = function() {

            console.log('clear success');

        }

    }

    function useCursorGetData() {

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName),

            *// request=store.openCursor();  //创建游标*

            *// request=store.openCursor(IDBKeyRange.only('002'));  //指定游标KeyRange，only一个*

            request = store.openCursor(null, 'prev');

        request.onsuccess = function() {

            var cursor = request.result;

            if (cursor) {

                console.log(cursor.value);

                cursor.continue();

            }

        }

    }

    function useIndexGetData() { *// 索引只能查询数据，并不能操作数据*

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName),

            *// request=store.openCursor();  //创建游标*

            *// request=store.openCursor(IDBKeyRange.only('002'));  //指定游标KeyRange，only一个*

            index = store.index('categoryIndex');

        request = index.getAll('飞行');

        request.onsuccess = function() {

            console.log(request.result);

        }

    }

    function useIndexAndCursorOperateData() { *// 索引和游标结合，可以查询和操作数据*

        var transaction = db.transaction(osName, 'readwrite'), *//打开一个事务，读写模式*

            store = transaction.objectStore(osName),

            *// request=store.openCursor();  //创建游标*

            *// request=store.openCursor(IDBKeyRange.only('002'));  //指定游标KeyRange，only一个*

            *// index=store.index('categoryIndex');*

            index = store.index('hpIndex');

        *// request = index.openCursor(IDBKeyRange.upperBound(5)); // 5（包含5）以下*

        request = index.openCursor(IDBKeyRange.bound(5,10,true,true)); *// 范围（5到10）*

        request.onsuccess = function() {

            var cursor = request.result,value=null;

            if (cursor) {

                *// if(cursor.value.id==='002'){*

                *// cursor.update({  // 更新数据*

                *//       name: '小蝙蝠',*

                *//       id: '002',*

                *//       hp: 10,*

                *//       category:['怪物','飞行']*

                *//     })* 

                *// cursor.delete().onsuccess=function () {  // 删除数据*

                *//   console.log('delete');*         

                *// }*        

                *// }*

                value = cursor.value;

                value.hp += 20;

                cursor.update(value);

                console.log(cursor.value);

                cursor.continue();

            }

        }

    }

    </script>

</body>

</html>