浏览器数据库工具类
此脚本不应直接安装。它是供其他脚本使用的外部库，要使用该库请加入元指令 // @require https://update.greatest.deepsurf.us/scripts/473362/1237033/Web%20IndexedDB%20Helper.js
// ==UserScript==
// @name Web IndexedDB Helper
// @namespace web-indexed-database-helper
// @version 1.0.0
// @description 浏览器数据库工具类
// @author 如梦Nya
// @license MIT
// @match *://*/*
// ==/UserScript==
class _WebIndexedDBHelper {
constructor() {
/** @type {IDBDatabase} */
this.db = undefined
}
/**
* 打开数据库
* @param {string} dbName 数据库名
* @param {number | undefined} dbVersion 数据库版本
* @returns {Promise<WebDB, any>}
*/
open(dbName, dbVersion) {
let self = this
return new Promise(function (resolve, reject) {
/** @type {IDBFactory} */
const indexDB = window.indexedDB || window.webkitIndexedDB || window.mozIndexedDB
let req = indexDB.open(dbName, dbVersion)
req.onerror = reject
req.onsuccess = function () {
self.db = this.result
resolve(self)
}
})
}
/**
* 查出一条数据
* @param {string} tableName 表名
* @param {string} key 键名
* @returns {Promise<any, any>}
*/
get(tableName, key) {
let self = this
return new Promise(function (resolve, reject) {
let req = self.db.transaction([tableName]).objectStore(tableName).get(key)
req.onerror = reject
req.onsuccess = function () {
resolve(this.result)
}
})
}
/**
* 插入、更新一条数据
* @param {string} tableName 表名
* @param {string} key 键名
* @param {any} value 数据
* @returns {Promise<IDBValidKey, any>}
*/
put(tableName, key, value) {
let self = this
return new Promise(function (resolve, reject) {
let req = self.db.transaction([tableName], 'readwrite').objectStore(tableName).put(value, key)
req.onerror = reject
req.onsuccess = function () {
resolve(this.result)
}
})
}
/**
* 关闭数据库
*/
close() {
this.db.close()
delete this.db
}
}
const WebDB = {
/**
* 打开数据库
* @param {string} dbName 数据库名
* @param {number | undefined} dbVersion 数据库版本
* @returns {Promise<WebDB, any>}
*/
open: function (dbName, dbVersion) {
return new _WebIndexedDBHelper().open(dbName, dbVersion)
}
}