83 lines
2.4 KiB
JavaScript
83 lines
2.4 KiB
JavaScript
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class ImageStore {
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constructor(dbName = 'imageDatabase', storeName = 'images') {
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this.dbName = dbName;
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this.storeName = storeName;
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this.db = null;
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}
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// 初始化IndexedDB数据库
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async initDB() {
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return new Promise((resolve, reject) => {
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const request = window.indexedDB.open(this.dbName, 1);
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request.onupgradeneeded = (event) => {
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const db = event.target.result;
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if (!db.objectStoreNames.contains(this.storeName)) {
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db.createObjectStore(this.storeName, { keyPath: 'url' });
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}
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};
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request.onsuccess = (event) => {
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this.db = event.target.result;
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resolve(this.db);
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};
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request.onerror = (event) => {
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console.error("Error opening IndexedDB:", event);
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reject(event);
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};
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});
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}
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// 存储Base64图片
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async storeImage(url, base64Data) {
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return new Promise(async (resolve, reject) => {
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if (!this.db) {
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await this.initDB();
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}
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const transaction = this.db.transaction([this.storeName], 'readwrite');
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const store = transaction.objectStore(this.storeName);
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const request = store.put({ url, base64Data });
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request.onsuccess = () => {
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resolve(true);
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};
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request.onerror = (event) => {
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console.error("Error storing image:", event);
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reject(event);
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};
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});
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}
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// 根据URL获取Base64图片
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async getImage(url) {
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return new Promise(async (resolve, reject) => {
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if (!this.db) {
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await this.initDB();
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}
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const transaction = this.db.transaction([this.storeName], 'readonly');
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const store = transaction.objectStore(this.storeName);
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const request = store.get(url);
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request.onsuccess = (event) => {
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const result = event.target.result;
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if (result) {
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resolve(result.base64Data);
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} else {
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resolve(null); // 如果没有找到图片，返回null
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}
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};
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request.onerror = (event) => {
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console.error("Error retrieving image:", event);
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reject(event);
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};
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});
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}
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}
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