Improvements of Vue3 over Vue2: better performance optimization

Improvements of Vue3 over Vue2: Better performance optimization

Vue is a popular JavaScript framework for building user interfaces. Its first few versions were famous for its concise and easy-to-use syntax and powerful responsive capabilities. However, as applications become more and more complex, Vue2 gradually reveals some problems in terms of performance. In order to solve these problems, Vue3 has undergone comprehensive improvements, with special emphasis on improving performance optimization. This article will introduce the improvements of Vue3 over Vue2 and provide some sample code to illustrate its advantages.

1. Faster rendering speed:
   Vue3 has made significant optimizations in rendering. In Vue2, the UI is updated through virtual DOM, which means that every time the data changes, the entire virtual DOM tree must be recalculated and compared with the actual DOM. This comparison will bring considerable performance overhead. Vue3 uses a Proxy-based tracking mechanism internally to update only the parts that have actually changed, thus greatly reducing rendering overhead. The following is a sample code that demonstrates the advantages of Vue3 in rendering speed compared to Vue2:

// Vue2
new Vue({
  data() {
    return {
      count: 0
    }
  },
  template: `
    <div>
      <span>{{ count }}</span>
      <button @click="count++">Increase</button>
    </div>
  `
}).$mount('#app')

// Vue3
createApp({
  data() {
    return {
      count: 0
    }
  },
  template: `
    <div>
      <span>{{ count }}</span>
      <button @click="count++">Increase</button>
    </div>
  `
}).mount('#app')

2. Smaller size:
   Vue3 has also made great improvements in terms of size. optimization. What is used in Vue2 is the inevitable full import. Even if you only use some of the functions, you need to import the entire library. Vue3 adopts a modular approach, splitting each function into independent modules, so that we only need to introduce the parts we need, thus reducing the size. The following is a sample code that demonstrates the size advantage of Vue3 over Vue2:

// Vue2
import Vue from 'vue'

Vue.component('MyComponent', {
  // ...
})

new Vue({
  // ...
})

// Vue3
import { createApp, defineComponent } from 'vue'

const MyComponent = defineComponent({
  // ...
})

createApp({
  // ...
}).component('MyComponent', MyComponent).mount('#app')

3. More powerful compiler:
   Vue3 provides a new compiler, which Significantly improved compilation performance. In Vue2, whenever we change a component's template, we need to recompile the entire template, which is very time-consuming for large projects. The Vue3 compiler will only compile the parts related to template changes, thus reducing the compilation overhead. The following is a sample code that demonstrates the advantages of Vue3 in compilation over Vue2:

// Vue2
<template>
  <div>
    <span>{{ count }}</span>
    <button @click="count++">Increase</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      count: 0
    }
  }
}
</script>

// Vue3
<template>
  <div>
    <span>{{ count }}</span>
    <button @click="count++">Increase</button>
  </div>
</template>

<script>
import { reactive } from 'vue'

export default {
  setup() {
    const count = reactive(0)
    return {
      count
    }
  }
}
</script>

In summary, Vue3 has made significant improvements in performance optimization compared to Vue2. Its faster rendering speed, smaller size, and more powerful compiler enable us to build more efficient applications. With the launch of Vue3, we can expect better user experience and higher development efficiency.

The above is the detailed content of Improvements of Vue3 over Vue2: better performance optimization. For more information, please follow other related articles on the PHP Chinese website!