React vs Vue 3 - JavaScript 框架语法对比

响应式

声明状态

React

import { useState } from "react";

export default function Name() {
  const [name] = useState("张三");

  return <h1>你好 {name}</h1>;
}

Vue 3

<script setup>
import { ref } from "vue";
const name = ref("张三");
</script>

<template>
  <h1>你好 {{ name }}</h1>
</template>

更新状态

React

import { useEffect, useState } from "react";

export default function Name() {
  const [name, setName] = useState("张三");

  useEffect(() => {
    setName("李四");
  }, []);

  return <h1>你好 {name}</h1>;
}

Vue 3

<script setup>
import { ref } from "vue";
const name = ref("张三");
name.value = "李四";
</script>

<template>
  <h1>你好 {{ name }}</h1>
</template>

计算属性

React

import { useState } from "react";

export default function DoubleCount() {
  const [count] = useState(10);
  const doubleCount = count * 2;

  return <div>{doubleCount}</div>;
}

Vue 3

<script setup>
import { ref, computed } from "vue";
const count = ref(10);
const doubleCount = computed(() => count.value * 2);
</script>

<template>
  <div>{{ doubleCount }}</div>
</template>

模板语法

最简模板

React

export default function HelloWorld() {
  return <h1>你好，世界</h1>;
}

Vue 3

<template>
  <h1>你好，世界</h1>
</template>

样式

React

import "./style.css";

export default function CssStyle() {
  return (
    <>
      <h1 className="title">我是红色的</h1>
      <button style={{ fontSize: "10rem" }}>我是一个按钮</button>
    </>
  );
}

Vue 3

<template>
  <h1 class="title">我是红色的</h1>
  <button style="font-size: 10rem">我是一个按钮</button>
</template>

<style scoped>
.title {
  color: red;
}
</style>

DOM循环

React

export default function Colors() {
  const colors = ["红", "绿", "蓝"];
  return (
    <ul>
      {colors.map((color) => (
        <li key={color}>{color}</li>
      ))}
    </ul>
  );
}

Vue 3

<script setup>
const colors = ["红", "绿", "蓝"];
</script>

<template>
  <ul>
    <li v-for="color in colors" :key="color">
      {{ color }}
    </li>
  </ul>
</template>

点击事件

React

import { useState } from "react";

export default function Counter() {
  const [count, setCount] = useState(0);

  function incrementCount() {
    setCount((count) => count + 1);
  }

  return (
    <>
      <p>计数器: {count}</p>
      <button onClick={incrementCount}>+1</button>
    </>
  );
}

Vue 3

<script setup>
import { ref } from "vue";
const count = ref(0);

function incrementCount() {
  count.value++;
}
</script>

<template>
  <p>计数器: {{ count }}</p>
  <button @click="incrementCount">+1</button>
</template>

DOM引用

React

import { useEffect, useRef } from "react";

export default function InputFocused() {
  const inputElement = useRef(null);

  useEffect(() => inputElement.current.focus(), []);

  return <input type="text" ref={inputElement} />;
}

Vue 3

<script setup>
import { useTemplateRef, onMounted } from "vue";

const inputElement = useTemplateRef("inputElement");

onMounted(() => {
  inputElement.value.focus();
});
</script>

<template>
  <input ref="inputElement" />
</template>

条件渲染

React

import { useState } from "react";

const TRAFFIC_LIGHTS = ["红灯", "黄灯", "绿灯"];

export default function TrafficLight() {
  const [lightIndex, setLightIndex] = useState(0);

  const light = TRAFFIC_LIGHTS[lightIndex];

  function nextLight() {
    setLightIndex((lightIndex + 1) % TRAFFIC_LIGHTS.length);
  }

  return (
    <>
      <button onClick={nextLight}>下一个灯</button>
      <p>现在亮着的是: {light}</p>
      <p>
        你应该
        {light === "红灯" && <span>停下</span>}
        {light === "黄灯" && <span>慢行</span>}
        {light === "绿灯" && <span>赶紧走</span>}
      </p>
    </>
  );
}

Vue 3

<script setup>
import { ref, computed } from "vue";
const TRAFFIC_LIGHTS = ["红灯", "黄灯", "绿灯"];
const lightIndex = ref(0);

const light = computed(() => TRAFFIC_LIGHTS[lightIndex.value]);

function nextLight() {
  lightIndex.value = (lightIndex.value + 1) % TRAFFIC_LIGHTS.length;
}
</script>

<template>
  <button @click="nextLight">下一个灯</button>
  <p>现在亮着的是: {{ light }}</p>
  <p>
    你应该
    <span v-if="light === '红灯'">停下</span>
    <span v-else-if="light === '黄灯'">慢行</span>
    <span v-else-if="light === '绿灯'">赶紧走</span>
  </p>
</template>

生命周期

组件加载时

React

import { useState, useEffect } from "react";

export default function PageTitle() {
  const [pageTitle, setPageTitle] = useState("");

  useEffect(() => {
    setPageTitle(document.title);
  }, []);

  return <p>页面标题: {pageTitle}</p>;
}

Vue 3

<script setup>
import { ref, onMounted } from "vue";
const pageTitle = ref("");
onMounted(() => {
  pageTitle.value = document.title;
});
</script>

<template>
  <p>页面标题: {{ pageTitle }}</p>
</template>

组件卸载时

React

import { useState, useEffect } from "react";

export default function Time() {
  const [time, setTime] = useState(new Date().toLocaleTimeString());

  useEffect(() => {
    const timer = setInterval(() => {
      setTime(new Date().toLocaleTimeString());
    }, 1000);

    return () => clearInterval(timer);
  }, []);

  return <p>当前时间: {time}</p>;
}

Vue 3

<script setup>
import { ref, onUnmounted } from "vue";

const time = ref(new Date().toLocaleTimeString());

const timer = setInterval(() => {
  time.value = new Date().toLocaleTimeString();
}, 1000);

onUnmounted(() => {
  clearInterval(timer);
});
</script>

<template>
  <p>当前时间: {{ time }}</p>
</template>

组件组合

组件Props传参

React

import UserProfile from "./UserProfile.jsx";

export default function App() {
  return (
    <UserProfile
      name="张三"
      age={20}
      favouriteColors={["green", "blue", "red"]}
      isAvailable
    />
  );
}

Vue 3

<script setup>
import UserProfile from "./UserProfile.vue";
</script>

<template>
  <UserProfile
    name="张三"
    :age="20"
    :favourite-colors="['green', 'blue', 'red']"
    is-available
  />
</template>

向父组件emit事件

React

import { useState } from "react";
import AnswerButton from "./AnswerButton.jsx";

export default function App() {
  const [isHappy, setIsHappy] = useState(true);

  function onAnswerNo() {
    setIsHappy(false);
  }

  function onAnswerYes() {
    setIsHappy(true);
  }

  return (
    <>
      <p>你快乐吗?</p>
      <AnswerButton onYes={onAnswerYes} onNo={onAnswerNo} />
      <p style={{ fontSize: 50 }}>{isHappy ? "😀" : "😥"}</p>
    </>
  );
}

Vue 3

<script setup>
import { ref } from "vue";
import AnswerButton from "./AnswerButton.vue";

let isHappy = ref(true);

function onAnswerNo() {
  isHappy.value = false;
}

function onAnswerYes() {
  isHappy.value = true;
}
</script>

<template>
  <p>你快乐吗?</p>
  <AnswerButton @yes="onAnswerYes" @no="onAnswerNo" />
  <p style="font-size: 50px">
    {{ isHappy ? "😀" : "😥" }}
  </p>
</template>

slot插槽

React

import FunnyButton from "./FunnyButton.jsx";

export default function App() {
  return <FunnyButton>点我!</FunnyButton>;
}

Vue 3

<script setup>
import FunnyButton from "./FunnyButton.vue";
</script>

<template>
  <FunnyButton> 点我! </FunnyButton>
</template>

slot插槽内容

React

import FunnyButton from "./FunnyButton.jsx";

export default function App() {
  return (
    <>
      <FunnyButton />
      <FunnyButton>这是传到slot的内容!</FunnyButton>
    </>
  );
}

Vue 3

<script setup>
import FunnyButton from "./FunnyButton.vue";
</script>

<template>
  <FunnyButton />
  <FunnyButton> 这是传到slot的内容! </FunnyButton>
</template>

上下文

React

import { useState } from "react";
import UserProfile from "./UserProfile";
import { UserContext } from "./UserContext";

export default function App() {
  const [user, setUser] = useState({
    id: 1,
    username: "abcdefg",
    email: "[email protected]",
  });

  function updateUsername(newUsername) {
    setUser((userData) => ({ ...userData, username: newUsername }));
  }

  return (
    <>
      <h1>欢迎回来, {user.username}</h1>
      <UserContext.Provider value={{ ...user, updateUsername }}>
        <UserProfile />
      </UserContext.Provider>
    </>
  );
}

Vue 3

<script setup>
import { ref, provide } from "vue";
import UserProfile from "./UserProfile.vue";

const user = ref({
  id: 1,
  username: "abcdefg",
  email: "[email protected]",
});

function updateUsername(username) {
  user.value.username = username;
}

provide("user", { user, updateUsername });
</script>

<template>
  <h1>欢迎回来, {{ user.username }}</h1>
  <UserProfile />
</template>

表单输入

输入框

React

import { useState } from "react";

export default function InputHello() {
  const [text, setText] = useState("你好世界");

  function handleChange(event) {
    setText(event.target.value);
  }

  return (
    <>
      <p>{text}</p>
      <input value={text} onChange={handleChange} />
    </>
  );
}

Vue 3

<script setup>
import { ref } from "vue";
const text = ref("你好世界");
</script>

<template>
  <p>{{ text }}</p>
  <input v-model="text" />
</template>

复选框

React

import { useState } from "react";

export default function IsAvailable() {
  const [isAvailable, setIsAvailable] = useState(false);

  function handleChange() {
    setIsAvailable(!isAvailable);
  }

  return (
    <>
      <input
        id="is-available"
        type="checkbox"
        checked={isAvailable}
        onChange={handleChange}
      />
      <label htmlFor="is-available">这是一个checkbox</label>
    </>
  );
}

Vue 3

<script setup>
import { ref } from "vue";

const isAvailable = ref(true);
</script>

<template>
  <input id="is-available" v-model="isAvailable" type="checkbox" />
  <label for="is-available">这是一个checkbox</label>
</template>

单选框

React

import { useState } from "react";

export default function PickPill() {
  const [picked, setPicked] = useState("red");

  function handleChange(event) {
    setPicked(event.target.value);
  }

  return (
    <>
      <div>你选择了: {picked}</div>

      <input
        id="blue-pill"
        checked={picked === "blue"}
        type="radio"
        value="blue"
        onChange={handleChange}
      />
      <label htmlFor="blue-pill">蓝色</label>

      <input
        id="red-pill"
        checked={picked === "red"}
        type="radio"
        value="red"
        onChange={handleChange}
      />
      <label htmlFor="red-pill">红色</label>
    </>
  );
}

Vue 3

<script setup>
import { ref } from "vue";

const picked = ref("red");
</script>

<template>
  <div>你选择了: {{ picked }}</div>

  <input id="blue-pill" v-model="picked" type="radio" value="blue" />
  <label for="blue-pill">蓝色</label>

  <input id="red-pill" v-model="picked" type="radio" value="red" />
  <label for="red-pill">红色</label>
</template>

选择器

React

import { useState } from "react";

const colors = [
  { id: 1, text: "红" },
  { id: 2, text: "蓝" },
  { id: 3, text: "绿" },
  { id: 4, text: "灰", isDisabled: true },
];

export default function ColorSelect() {
  const [selectedColorId, setSelectedColorId] = useState(2);

  function handleChange(event) {
    setSelectedColorId(event.target.value);
  }

  return (
    <select value={selectedColorId} onChange={handleChange}>
      {colors.map((color) => (
        <option key={color.id} value={color.id} disabled={color.isDisabled}>
          {color.text}
        </option>
      ))}
    </select>
  );
}

Vue 3

<script setup>
import { ref } from "vue";

const selectedColorId = ref(2);

const colors = [
  { id: 1, text: "红" },
  { id: 2, text: "蓝" },
  { id: 3, text: "绿" },
  { id: 4, text: "灰", isDisabled: true },
];
</script>

<template>
  <select v-model="selectedColorId">
    <option
      v-for="color in colors"
      :key="color.id"
      :value="color.id"
      :disabled="color.isDisabled"
    >
      {{ color.text }}
    </option>
  </select>
</template>

Web应用特性

渲染应用

React

<!doctype html>
<html>
  <body>
    <div id="app"></div>
    <script type="module" src="./main.jsx"></script>
  </body>
</html>

Vue 3

<!doctype html>
<html>
  <body>
    <div id="app"></div>
    <script type="module" src="./main.js"></script>
  </body>
</html>

fetch获取数据

React

import useFetchUsers from "./useFetchUsers";

export default function App() {
  const { isLoading, error, data: users } = useFetchUsers();

  return (
    <>
      {isLoading ? (
        <p>正在获取用户信息……</p>
      ) : error ? (
        <p>获取用户信息出错</p>
      ) : (
        users && (
          <ul>
            {users.map((user) => (
              <li key={user.login.uuid}>
                <img src={user.picture.thumbnail} alt="user" />
                <p>
                  {user.name.first} {user.name.last}
                </p>
              </li>
            ))}
          </ul>
        )
      )}
    </>
  );
}

Vue 3

<script setup>
import useFetchUsers from "./useFetchUsers";

const { isLoading, error, data: users } = useFetchUsers();
</script>

<template>
  <p v-if="isLoading">正在获取用户信息……</p>
  <p v-else-if="error">获取用户信息出错</p>
  <ul v-else-if="users">
    <li v-for="user in users" :key="user.login.uuid">
      <img :src="user.picture.thumbnail" alt="user" />
      <p>
        {{ user.name.first }}
        {{ user.name.last }}
      </p>
    </li>
  </ul>
</template>

响应式 #

声明状态 #

React

Vue 3

更新状态 #

React

Vue 3

计算属性 #

React

Vue 3

模板语法 #

最简模板 #

React

Vue 3

样式 #

React

Vue 3

DOM循环 #

React

Vue 3

点击事件 #

React

Vue 3

DOM引用 #

React

Vue 3

条件渲染 #

React

Vue 3

生命周期 #

组件加载时 #

React

Vue 3

组件卸载时 #

React

Vue 3

组件组合 #

组件Props传参 #

React

Vue 3

向父组件emit事件 #

React

Vue 3

slot插槽 #

React

Vue 3

slot插槽内容 #

React

Vue 3

上下文 #

React

Vue 3

表单输入 #

输入框 #

React

Vue 3

复选框 #

React

Vue 3

单选框 #

React

Vue 3

选择器 #

React

Vue 3

Web应用特性 #

渲染应用 #

React

Vue 3

fetch获取数据 #

React

Vue 3

响应式

声明状态

更新状态

计算属性

模板语法

最简模板

样式

DOM循环

点击事件

DOM引用

条件渲染

生命周期

组件加载时

组件卸载时

组件组合

组件Props传参

向父组件emit事件

slot插槽

slot插槽内容

上下文

表单输入

输入框

复选框

单选框

选择器

Web应用特性

渲染应用

fetch获取数据