我正在尝试创建一个数据管理应用程序，但我使用的是 IndexedDB，而不是基于 Windows 的解决方案或使用 WebSQL。我对它很陌生，但我相信我已经涵盖了这个代码草案的基础。
无论如何，我的问题是，每当我运行代码时，我的 openDB() 函数和 addeventListener() 函数都会在运行时运行并显示在控制台日志上，但是当我尝试运行代码时，据说所有其他函数都是未定义的。问题可能是什么？
在 HTML 文件中，引用了 jQuery 脚本文件。
(function () {
var DB_NAME = 'shodex';
var DB_VERSION = 1;
var DB_STORE_NAME = 'visitors';
var db;
var current_view_pub_key;
//opens the IndexedDB database
function openDb() {
console.log("open Database......");
var req = indexedDB.open(DB_NAME, DB_VERSION);
req.onsuccess = function (evt) {
db = this.result;
console.log("Database Opened");
};
req.onerror = function (evt) {
console.error("openDb:", evt.target.errorCode);
};
req.onupgradeneeded = function (evt) {
console.log("Event fired when DB is needed to be upgraded");
var store = evt.currentTarget.result.createObjectStore(
DB_STORE_NAME, { keyPath: 'id', autoIncrement: true });
store.createIndex('name', 'name', { unique: false });
store.createIndex('date', 'date', { unique: false });
store.createIndex('whom_to_see', 'whom_to_see', { unique: false });
store.createIndex('arrival_time', 'arrival_time', { unique: false });
store.createIndex('reason', 'reason', { unique: false });
store.createIndex('departure_time', 'departure_time', { unique: false });
};
}
//used to create a transaction
function getObjectStore(store_name, mode) {
var tx = db.transaction(store_name, mode);
return tx.objectStore(store_name);
}
//adds a Visitor to the IndexedDB
function addVisitor(name, date, to_see, arrival_time, reason, departure_time) {
console.log("Adding the following data to IndexedDB: ", arguments);
var obj = { name: name, date: date, whom_to_see: to_see, arrival_time: arrival_time, reason: reason, departure_time: departure_time };
if(typeof blob != undefined)
{
obj.blob = blob;
}
var store = getObjectStore(DB_STORE_NAME, 'readwrite');
var req;
try
{
req = store.add(obj);
}
catch(e)
{
if(e.name == 'DataCloneError')
displayActionFailure("This engine does not know how to clone a Blob, use Firefox!");
throw(e);
}
req.onsuccess = function (evt) {
console.log("Insertion into DB was successful. You can heave a huge sigh of relief!");
displayActionSuccess();
};
req.onerror = function () {
console.error("Insertion into DB failed!");
displayActionFailure(this.error);
};
}
function displayActionSuccess() {
alert("Whatever the heck you were doing was successful. Congrats!");
}
function displayActionFailure() {
alert("Oh Oh! System Failure! System Failure!");
}
// listens for the submit button event
function addEventListeners() {
console.log("Event Listeners");
$('#addVisitor').click(function(evt) {
console.log("Add Visitors Submit button");
var name = document.getElementsByName("txtName").value;
var date = document.getElementsByName("txtDate").value;
var whom_to_see = document.getElementsByName("txtToSee").value;
var time_of_arrival = document.getElementsByName("txtArrivalTime").value;
var reason_for_visit = document.getElementsByName("txtReason").value;
var time_of_departure = document.getElementsByName("timeOfDep");
addVisitor(name, date, whom_to_see, time_of_arrival, reason_for_visit, time_of_departure);
});
}
//makes the database open at runtime
openDb();
addEventListeners();
})
();