Add locale questions

Author: sudheerj

README.md

@@ -218,6 +218,7 @@ List of 300 VueJS Interview Questions
 |209| [How do you handle Pluralization?](#how-do-you-handle-pluralization)|
 |210| [How to implement DateTime localization?](#how-to-implement-date-time-localization)|
 |211| [How do you implement Number localization?](#how-do-you-implement-number-localization)|
+|212| [How do you perform locale changing](#how-do-you-perform-locale-changin)|
 
 1. ### What is VueJS?
  **Vue.js** is an open-source, progressive Javascript framework for building user interfaces that aim to be incrementally adoptable. The core library of VueJS is focused on the `view layer` only, and is easy to pick up and integrate with other libraries or existing projects.
@@ -3816,5 +3817,41 @@ List of 300 VueJS Interview Questions
  <p>￥50</p>
  </div>
  ```
+212. ### How do you perform locale changing?
+ All child components of a root instance are localized using the locale property of the VueI18n class. You can change the value of the locale property of the VueI18n instance as below.
+ ```javascript
+ const i18n = new VueI18n({
+ locale: 'de', // set locale
+ ...
+ })
+
+ // create root Vue instance
+ new Vue({
+ i18n,
+ ...
+ }).$mount('#app')
+
+ // change other locale
+ i18n.locale = 'en'
+ ```
+ You can also use component's VueI18n instance referenced as the $i18n property which will be used to change the locale.
+ ```javascript
+ <template>
+ <div class="locale-changer">
+ <select v-model="$i18n.locale">
+ <option v-for="(lang, i) in langs" :key="`Lang${i}`" :value="lang">{{ lang }}</option>
+ </select>
+ </div>
+ </template>
+
+ <script>
+ export default {
+ name: 'locale-changer',
+ data () {
+ return { langs: ['de', 'en'] }
+ }
+ }
+ </script>
+ ```