react中createContext以及useContext的简单使用

1、在父组件中定义数据

在这里需要特别注意的是：定义createContext后需要导出，在其他页面必须要引入才可以使用

import React, { Suspense, createContext } from "react";
import { ContextA } from "./components/ContextA";
import { ContextB } from "./components/ContextB";
export const CountContext = createContext({
	name: "杨幂",
	age: 12,
	sex: "女",
});
export const App = () => {
	return (
		<Suspense fallback={<div>数据正在加载中。。。</div>}>
			<CountContext.Provider value={{ sex: "女", name: "杨幂", age: 12 }}>
				<ContextA />
				<ContextB />
			</CountContext.Provider>
		</Suspense>
	);
};

2、子组件页面

import React, { useContext } from "react";
import { CountContext } from "../App";//将父组件中定义的进行导入
export const ContextA = () => {
	const message = useContext(CountContext);
	return (
		<div>
			{message?.name} - {message?.age} -{message?.sex}
		</div>
	);
};