鍦╒ue3涓紝鍙互浣跨敤`setup`鍑芥暟鏉ヤ唬鏇縑ue2涓殑`beforeCreate`鍜宍created`鐢熷懡鍛ㄦ湡閽╁瓙鍑芥暟銆俙setup`鍑芥暟鏄竴涓櫘閫氱殑JavaScript鍑芥暟锛屽畠鎺ユ敹涓や釜鍙傛暟锛歚props`鍜宍context`銆?br/>`props`鍙傛暟鏄竴涓搷搴斿紡瀵硅薄锛屽寘鍚簡缁勪欢鎺ユ敹鍒扮殑props灞炴€с€備綘鍙互鍦╜setup`鍑芥暟涓洿鎺ヤ娇鐢╜props`瀵硅薄銆?br/>`context`鍙傛暟鏄竴涓笂涓嬫枃瀵硅薄锛屽寘鍚簡涓€浜涘父鐢ㄧ殑灞炴€у拰鏂规硶锛屾瘮濡俙attrs`銆乣emit`銆乣slots`绛夈€備綘鍙互閫氳繃`context`瀵硅薄鏉ヨ闂繖浜涘睘鎬у拰鏂规硶銆?br/>涓嬮潰鏄竴涓娇鐢╜setup`鍑芥暟鐨勪緥瀛愶細
```javascript
import { ref } from 'vue';

export default {
 props: ['message'],
 setup(props, context) {
   const count = ref(0);

   function increment() {
     count.value++;
   }

   return {
     count,
     increment
   };
 }
};
```
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```html

```
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