indexdb 代码直接可用

<pre>
var DB = {
scheme: {
//timetag: {key: {keyPath: "name"}},
//blacklist: {key: {keyPath: "account"}},
//mutelist: {key: {keyPath: "account"}},
//friend: {key: {keyPath: "account"}},
//user: {key: {keyPath: "account"}},
//team: {key: {keyPath: "teamId"}},
//teamMember: {key: {keyPath: "id"}, indexes: {teamId: {unique: !1}}},
//msg: {
// key: {autoIncrement: !0},
// indexes: {
// idClient: {unique: !0},
// sessionId: {unique: !1},
// time: {unique: !1},
// type: {unique: !1},
// sessionType: {unique: !1}
// }
//},
//sysMsg: {
// key: {autoIncrement: !0},
// indexes: {idServer: {unique: !0}, category: {unique: !1}, type: {unique: !1}}
//},
//sysMsgUnread: {key: {keyPath: "type"}},
settings: {
key: {keyPath: 'name'}
},
CustomMsg: {
key: {keyPath: "time"}
}
},
init: function (table_name) {
var that = this
that.db_name = 'test-mydb'
that.db_version = 1
that.db = false;
that.table_name = table_name || 'CustomMsg'
that.request = that.request || indexedDB.open(that.db_name, that.db_version);
that.tables = Object.keys(that.scheme)

    that.request.onupgradeneeded = function (e) {
        console.log("db Upgrading...");
        var thisDB = e.target.result;
        for (var r in that.scheme) {
            var table, setting = that.scheme[r];
            table = thisDB.objectStoreNames.contains(r) ? e.currentTarget.transaction.objectStore(r) : thisDB.createObjectStore(r, setting.key);
            for (var a in setting.indexes) {
                var s = setting.indexes[a];
                try {
                    table.index(a)
                } catch (e) {
                    table.createIndex(a, s.key || a, Object.keys(s).length ? s : {unique: !1})
                }
            }
        }
    }

    that.request.onsuccess = function (e) {
        console.log("db Success!");
        that.db = e.target.result;
    }

    that.request.onerror = function (e) {
        console.log("Error");
        console.dir(e);
    }
    return that
},
insert: function (data, callback) {
    var request = this.db.transaction([this.table_name], "readwrite").objectStore(this.table_name).add(data);
    request.onerror = function (e) {
        console.log("Error", e.target.error.name);
    }
    request.onsuccess = function (e) {
        console.log('insert ok')
        if (callback != null)
            callback.call()
    }
},
update: function (data, callback) {
    var request = this.db.transaction([this.table_name], "readwrite").objectStore(this.table_name).put(data);
    request.onerror = function (e) {
        console.log("Error", e.target.error.name);
    }
    request.onsuccess = function (e) {
        if (callback != null)
            callback.call()
    }
},
read: function (key, callback) {
    var request = this.db.transaction([this.table_name], "readonly").objectStore(this.table_name).get(key);
    request.onerror = function (e) {
        console.log("Error", e.target.error.name);
    }
    request.onsuccess = function (e) {
        if (callback != null)
            callback.call()
    }
},
read_all: function (callback) {
    var cursor = this.db.transaction([this.table_name], "readonly").objectStore(this.table_name).openCursor(),
        result = [];
    cursor.onsuccess = function (e) {
        var res = e.target.result
        if (res) {
            result.push(res.value);
            res.continue();
        } else {
            if (callback != null)
                callback.call(this, result)
        }
    }
},
delete: function (key, callback) {
    var request = this.db.transaction([this.table_name], "readwrite").objectStore(this.table_name).delete(key)
    request.onerror = function (e) {
        console.log("Error", e.target.error.name);
    }
    request.onsuccess = function (e) {
        if (callback != null)
            callback.call()
    }
}

}</pre>

我们可以给这段代码复制到浏览器的console里，然后试用一下：
<pre>
//初始化数据
var CustomMsg = DB.init('CustomMsg')
//插入数据
CustomMsg.insert({time:(new Date().getTime()),from:'zhang',to:'wang',content:'你好'})
CustomMsg.insert({time:(new Date().getTime()),from:'wang',to:'zhang',content:'你也好啊'})
//读数据
CustomMsg.read_all(function(result){console.log(result)})
//删除
CustomMsg.delete(1472780909969)
</pre>

Paste_Image.png 读取数据 删除数据

使用indexDb有一些需要注意的点：

1. 必须增大db_version才能增加表（本篇默认version 1，生成两张表）
2. 指定主键以后，update的功效更insert一样了
3. 异步，indexdb的东西基本都是异步操作，数据都是在回调里！也就是说刚insert和read同时写上去，read是看不到数据的
4. 比较复杂的索引与查询，请参考 http://www.cnblogs.com/dolphinX/p/3416889.html