updateScore()
让我们首先为我们的函数声明一个类型
// @/types/score.ts
export type ScoreType = { points: number };
export type UpdateScoreFunction = (val: ScoreType) => void;
现在我们需要声明一个InjectionKey
它将保存我们提供/注入的变量(在本例中为函数)的类型信息。更多关于它的信息在Vue 文档中
让我们创建一个单独的文件夹来存储我们的密钥并保持事物井井有条:
// @/symbols/score.ts
import { InjectionKey } from "vue";
import { UpdateScoreFunction } from "@/types/score";
export const updateScoreKey: InjectionKey<UpdateScoreFunction> = Symbol("updateScore");
在我们的父组件中(A)
:
<script lang="ts">
import { defineComponent, provide, ref } from "vue";
import { ScoreType, UpdateScoreFunction } from "@/types/score";
import { updateScoreKey } from "@/symbols/score";
export default defineComponent({
setup() {
const score = ref<ScoreType[]>([]);
// Actually, adding ': UpdateScoreFunction' is optional
const updateScore: UpdateScoreFunction = function (val: ScoreType) {
score.value.push(val);
};
// Replace the string with InjectionKey
provide(updateScoreKey, updateScore);
// ...
},
});
</script>
在我们的子组件中(B)
:
<script lang="ts">
import { defineComponent, inject } from "vue";
import { updateScoreKey } from "@/symbols/score";
export default defineComponent({
setup() {
// Replace the string with InjectionKey
const updateScore = inject(updateScoreKey);
// In case the `updateScoreKey` is not provided by the parent component..
if (updateScore === undefined) {
throw new Error('Failed to inject "updateScore"');
}
const checkAnswer = (val: string) => {
// ...
// The error is gone
updateScore({
points: Math.floor(Math.random() * 100),
});
};
// ...
},
});
</script>
此处提供的工作示例:codesandbox.io/s/so-provide-inject