类型安全的国际化：i18n类型实现综合指南

            
// src/i18n/locales/en/translation.d.ts
interface Translation {
  greeting: string;
  welcomeMessage: string;
  userProfile: {
    name: string;
    age: string;
    location: string;
  };
  // ... other translations
}

export default Translation;

            

              
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// src/i18n/locales/en/translation.json
{
  "greeting": "Hello",
  "welcomeMessage": "Welcome to our website!",
  "userProfile": {
    "name": "Name: {{name}}",
    "age": "Age: {{age}}",
    "location": "Location: {{location}}"
  }
  // ... other translations
}

            

              
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// src/i18n/i18n.ts
import i18n from 'i18next';
import { initReactI18next } from 'react-i18next';
import translationEN from './locales/en/translation.json';
import translationDE from './locales/de/translation.json';
import Translation from './locales/en/translation'; // Import the type definition

// Explicitly define resource types to ensure type safety
interface Resources {
  en: {
    translation: typeof translationEN;
  };
  de: {
    translation: typeof translationDE;
  };
}

i18n
  .use(initReactI18next)
  .init({  // Explicitly type i18n.init
    resources: {
      en: {
        translation: translationEN
      },
      de: {
        translation: translationDE
      }
    },
    lng: 'en',
    fallbackLng: 'en',
    interpolation: {
      escapeValue: false
    }
  });

export default i18n;

            

              
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// src/components/UserProfile.tsx
import React from 'react';
import { useTranslation } from 'react-i18next';
import Translation from '../i18n/locales/en/translation';

interface Props {
  name: string;
  age: number;
  location: string;
}

const UserProfile: React.FC = ({ name, age, location }) => {
  const { t } = useTranslation<'translation', undefined, Translation>();

  return (
    

      
{t('userProfile.name', { name })}
      
{t('userProfile.age', { age })}
      
{t('userProfile.location', { location })}
    
  );
};

export default UserProfile;

            

              
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// Define message descriptors with types
interface MessageDescriptor {
  id: string;
  defaultMessage: string;
  description?: string;
}

const messages: {
  [key: string]: MessageDescriptor;
} = {
  greeting: {
    id: 'app.greeting',
    defaultMessage: 'Hello, {name}!',
    description: 'A simple greeting message',
  },
  // ... more messages
};

// Use formatMessage with typed messages
import { createIntl, createIntlCache } from '@formatjs/intl';

const cache = createIntlCache();
const intl = createIntl(
  {
    locale: 'en',
    messages: {
      [messages.greeting.id]: messages.greeting.defaultMessage,
    },
  },
  { cache }
);

// Usage
const formattedMessage = intl.formatMessage(messages.greeting, { name: 'John' });
console.log(formattedMessage); // Output: Hello, John!

            

              
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