How to perform DOM manipulation in Uni-app

Uni-app is a framework that can quickly develop cross-platform applications. It supports multiple platforms, such as WeChat applet, APP, H5, etc. Compared with using native development, it can greatly improve development efficiency and code reusability. However, in development, we inevitably need to perform DOM operations, so in this article, we will discuss how to perform DOM operations in Uni-app.

DOM operation refers to modifying the Document Object Model (Document Object Model). In Uni-app, the implementation of DOM operations is similar to that in ordinary web applications, but there are some slight differences. Uni-app mainly uses two methods for DOM operations: Vue's own instructions, and js code operations.

First let’s look at the instructions that come with Vue. Vue comes with many instructions, such as v-if, v-for, v-on, etc. Through these instructions, we can easily perform DOM operations. Taking v-if as an example, we can use this instruction to control whether an element is hidden. The following is a simple example:

<template>
  <div>
    <div v-if="isShow">这是一个显示的元素</div>
    <button @click="changeIsShow">点击切换</button>
  </div>
</template>
<script>
  export default {
    data() {
      return {
        isShow: true,
      };
    },
    methods: {
      changeIsShow() {
        this.isShow = !this.isShow;
      },
    },
  };
</script>

In the above code, we use the v-if directive to determine whether to display "This is a displayed element". When isShow is true, the element will be displayed, otherwise it will be hidden. At the same time, we also use a button to change the value of isShow to display and hide elements.

In addition to the v-if instruction, there are other instructions that can also implement DOM operations. For example, v-for can be used to loop through an array or object and render the corresponding element; v-bind can be used to bind the attributes or styles of elements; v-on can be used to listen to an event, etc. How to use these instructions can be found in the Vue official documentation.

Of course, sometimes we need to operate the DOM more flexibly, then we need to use js code to operate. In Uni-app, we can use native JS for DOM manipulation just like in a normal web application. The following is a simple example:

<template>
  <div>
    <div ref="test">这是一个元素</div>
    <button @click="changeElement">点击修改元素</button>
  </div>
</template>
<script>
  export default {
    methods: {
      changeElement() {
        const test = this.$refs.test;
        test.style.color = 'red';
        test.innerText = '这是一个修改过的元素';
      },
    },
  };
</script>

In the above code, we first use the ref attribute on the div element. The function of this attribute is to set a reference for the element, which is convenient for us to call in JS code . In the changeElement method, we obtain the element through this.$refs.test, and modify its text and color to realize the modification of the element.

In addition to modifying the text and style of elements, we can also use some other JS APIs to perform DOM operations, such as appendChild, removeChild, insertBefore, etc., which will not be listed here.

In summary, to perform DOM operations in Uni-app, we can either use Vue's own instructions or use the native JS API to operate. No matter which method is used, attention needs to be paid to code readability and performance issues to ensure the stability and efficiency of the application.

The above is the detailed content of How to perform DOM manipulation in Uni-app. For more information, please follow other related articles on the PHP Chinese website!