indexDB问题：evt.target.result为null？

Question

我的代码如下：

var indexedDB = window.msIndexedDB;

adsageIDB = {};
adsageIDB.db = null;

adsageIDB.onerror = function (e) {
    console.log(e);
};

adsageIDB.open = function () {
    var request = indexedDB.open("adsageIDB", 1);

    request.onsuccess = function (evt) {
        adsageIDB.db = evt.target.result;
        var db = adsageIDB.db;
        if (db.objectStoreNames.contains("todo")) {
            db.deleteObjectStore("todo");
        }
        var store = db.createObjectStore("todo",{ keyPath: "adsid" });

    };
    request.onerror = function (evt) {
        console.log("Database error code:" + evt.target.errorCode);
    };
}

环境是win8下的 javascript metro app，运行后 adsageIDB.db 一直为空，请问是哪儿写的有问题？

Answer 1

adsageIDB.open()执行了吗？没有看到调用代码呀