add i18n step1

frontend/js/locale.js

@@ -10,7 +10,7 @@ const supportedLangs = ['en', 'zh-CN']; // 应用支持的语言列表
  */
 async function loadLocale(lang) {
     try {
-        const response = await fetch(`/locales/${lang}.json?v=${Date.now()}`);
+        const response = await fetch(`/locales/${lang}.json`);
         if (!response.ok) {
             throw new Error(`Language file for ${lang} not found (status: ${response.status}).`);
         }
@@ -49,7 +49,14 @@ function applyTranslationsToDOM() {
     document.querySelectorAll('[data-i18n-title]').forEach(el => {
         const key = el.dataset.i18nTitle;
         const translation = t(key);
-        if(translation !== key) el.title = translation;
+        if (translation !== key) el.title = translation;
+    });
+    document.querySelectorAll('[data-i18n-placeholder]').forEach(el => {
+        const key = el.dataset.i18nPlaceholder;
+        const translation = t(key);
+        if (translation !== key && el.placeholder !== undefined) { // 确保元素有placeholder属性
+            el.placeholder = translation;
+        }
     });
 }
 
@@ -62,7 +69,7 @@ function applyTranslationsToDOM() {
 export function t(key, replacements = {}) {
     // 通过路径 'a.b.c' 在嵌套对象中查找值: currentLocale['a']['b']['c']
     const translation = key.split('.').reduce((obj, k) => obj && obj[k], currentLocale);
-    
+
     let result = translation || key; // 如果找不到, 返回原始key作为回退
 
     // 处理占位符替换, e.g., {filename: 'example.com'}
@@ -71,7 +78,7 @@ export function t(key, replacements = {}) {
             result = result.replace(`{${placeholder}}`, replacements[placeholder]);
         }
     }
-    
+
     return result;
 }
 
@@ -106,4 +113,8 @@ export async function setLanguage(lang) {
         localStorage.setItem('appLanguage', lang);
         window.location.reload(); // 刷新页面以应用所有翻译是最简单可靠的方式
     }
+}
+
+export function getCurrentLanguage() {
+    return currentLang;
 }