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Web IndexedDB Helper

浏览器数据库工具类

Tento skript by neměl být instalován přímo. Jedná se o knihovnu, kterou by měly jiné skripty využívat pomocí meta příkazu // @require https://update.greatest.deepsurf.us/scripts/473362/1237033/Web%20IndexedDB%20Helper.js 

  1. // ==UserScript==
  2. // @name        Web IndexedDB Helper
  3. // @namespace   web-indexed-database-helper
  4. // @version     1.0.0
  5. // @description 浏览器数据库工具类
  6. // @author      如梦Nya
  7. // @license     MIT
  8. // @match       *://*/*
  9. // ==/UserScript==
  10.  
  11. class _WebIndexedDBHelper {
  12.     constructor() {
  13.         /** @type {IDBDatabase} */
  14.         this.db = undefined
  15.     }
  16.  
  17.     /**
  18.      * 打开数据库
  19.      * @param {string} dbName 数据库名
  20.      * @param {number | undefined} dbVersion 数据库版本
  21.      * @returns {Promise<WebDB, any>}
  22.      */
  23.     open(dbName, dbVersion) {
  24.         let self = this
  25.         return new Promise(function (resolve, reject) {
  26.             /** @type {IDBFactory} */
  27.             const indexDB = window.indexedDB || window.webkitIndexedDB || window.mozIndexedDB
  28.             let req = indexDB.open(dbName, dbVersion)
  29.             req.onerror = reject
  30.             req.onsuccess = function () {
  31.                 self.db = this.result
  32.                 resolve(self)
  33.             }
  34.         })
  35.     }
  36.  
  37.     /**
  38.      * 查出一条数据
  39.      * @param {string} tableName 表名
  40.      * @param {string} key 键名
  41.      * @returns {Promise<any, any>}
  42.      */
  43.     get(tableName, key) {
  44.         let self = this
  45.         return new Promise(function (resolve, reject) {
  46.             let req = self.db.transaction([tableName]).objectStore(tableName).get(key)
  47.             req.onerror = reject
  48.             req.onsuccess = function () {
  49.                 resolve(this.result)
  50.             }
  51.         })
  52.     }
  53.  
  54.     /**
  55.      * 插入、更新一条数据
  56.      * @param {string} tableName 表名
  57.      * @param {string} key 键名
  58.      * @param {any} value 数据
  59.      * @returns {Promise<IDBValidKey, any>}
  60.      */
  61.     put(tableName, key, value) {
  62.         let self = this
  63.         return new Promise(function (resolve, reject) {
  64.             let req = self.db.transaction([tableName], 'readwrite').objectStore(tableName).put(value, key)
  65.             req.onerror = reject
  66.             req.onsuccess = function () {
  67.                 resolve(this.result)
  68.             }
  69.         })
  70.     }
  71.  
  72.     /**
  73.      * 关闭数据库
  74.      */
  75.     close() {
  76.         this.db.close()
  77.         delete this.db
  78.     }
  79. }
  80.  
  81. const WebDB = {
  82.     /**
  83.      * 打开数据库
  84.      * @param {string} dbName 数据库名
  85.      * @param {number | undefined} dbVersion 数据库版本
  86.      * @returns {Promise<WebDB, any>}
  87.      */
  88.     open: function (dbName, dbVersion) {
  89.         return new _WebIndexedDBHelper().open(dbName, dbVersion)
  90.     }
  91. }