23 lines
342 B
JavaScript
23 lines
342 B
JavaScript
import { useState } from "react";
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// 子组件
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function Child() {
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console.log("child render");
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return <span>child</span>;
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}
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// 父组件
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function App() {
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const [num, updateNum] = useState(0);
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console.log("App render", num);
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return (
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<div onClick={() => updateNum(1)}>
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<Child />
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</div>
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);
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}
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export default App;
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