Vue3 learning in-depth analysis of CSS Modules and Scope

Css Modules is to add the label class name into a unique class name, for example, .class is converted into .class_abc_123, similar to symbol, unique key name

Css Scope achieves scope isolation by adding a custom attribute to an element and adding a unique number to this attribute.

Principle

##CSS Modules

CSS ModulesThe principle of implementing CSS modularization is based on what we defined in the config file

Class name naming rules generate a unique name for the class to achieve scope isolation. [Related recommendations: vuejs video tutorial, web front-end development]

Before conversion

• <style module>
    .title {
      font-size: 14px;
      font-family: Microsoft YaHei, Microsoft YaHei-Bold;
      font-weight: 700;
      color: #13161b;
    }
    .name {
      display: flex;
      align-items: center;
      &-img {
        width: 24px;
        height: 24px;
        border-radius: 4px;
      }
      &-text {
        font-size: 14px;
        font-family: Microsoft YaHei, Microsoft YaHei-Regular;
        font-weight: 400;
        color: #13161b;
      }
    }
  </style>

     cell: (h, { col, row }) => {
        // console.log(style);
        return (
          <span class={style.name}>
            <img src={testImage} class={style[&#39;name-img&#39;]} />
            <span class={style[&#39;name-text&#39;]}>{row.name}</span>
          </span>
        );
      },

After conversion

The tag.name-img is converted into _name_img_6hlfj_11 etc.

Scoped CSS

Vue Loader uses the CSS post-processor PostCSS by default to implement Scoped CSS. The principle is to add a custom attribute to the element hit by the selector in the style declared scoped, and then use the attribute selector to achieve the effect of scope isolation style.

Before conversion

<template>
  <div class="example">hi</div>
</template>
<style module>
.example {
  color: red;
}
</style>

After conversion

<!-- 用自定义属性把类名封装起来了 -->
<style>
.example[data-v-f3f3eg9] {
  color: red;
}
</style>
<template>
  <div class="example" data-v-f3f3eg9>hi</div>
</template>

Apply

CSS Modules

About application, here we only introduce the usage issues in the Vue3 version

In Vue3, CSS Modules, in