Debugging tool functions in Vue3: Let you debug Vue3 code more conveniently

Vue3 is a popular JavaScript framework that is popular among many developers due to its ease of use and flexibility. For developers, debugging code is an indispensable task, and good debugging tools can help us get twice the result with half the effort. In Vue3, we can use some practical debugging tool functions to debug code more conveniently. This article will introduce some debugging tool functions in Vue3 to help you better debug your Vue3 code.

1. $refs

In Vue3, we can use $refs to access DOM elements or subcomponent instances in components. This feature is very useful when debugging. When we need to debug a child DOM element in a component, we only need to set the ref attribute for the element in the Vue template, and then we can access the DOM element through $refs in the component instance.

For example, we have a Button component that contains a button element as its child element. We can add the ref attribute to the Vue template:

<template>
  <div>
    <button ref="myButton">Click Me</button>
  </div>
</template>

Then, in the component instance, we can use $refs to access the button element:

<script>
  export default {
    mounted() {
      const button = this.$refs.myButton
      console.log(button) // 输出<button>Click Me</button>
    }
  }
</script>

Through $refs, we can easily Access DOM elements or subcomponent instances within components to better debug our Vue3 code.

2. $options

There is also a utility function $options in Vue3, which allows us to access the options of the Vue component, including templates, component names, component data, Lifecycle hooks and more. When debugging, this function can help us better understand the various properties and methods in the component, so as to better locate the problem.

For example, we have a MyComponent component that contains some data and methods. We can view the options of this component through $options:

<script>
  export default {
    data() {
      return {
        message: "Hello World"
      }
    },
    methods: {
      logMessage() {
        console.log(this.message)
      }
    },
    mounted() {
      console.log(this.$options) // 输出组件的全部选项
    }
  }
</script>

Through $options, we can view all options of the component to better understand the structure and function of the component.

3. $emit

In Vue3, $emit is a method used to trigger component custom events. We can use $emit to send custom events, and then perform corresponding logic by listening to the event elsewhere. When debugging, this method conveniently allows us to simulate various events and check the correctness of the listener.

For example, we have a MyButton component, which contains a button element. We can bind a click event to the button element and trigger a custom event through $emit when clicked:

<template>
  <div>
    <button @click="handleClick">Click Me</button>
  </div>
</template>

<script>
  export default {
    methods: {
      handleClick() {
        this.$emit("my-event")
      }
    }
  }
</script>

Then, in the parent component, we can execute it by listening to the custom event Corresponding logic:

<template>
  <div>
    <MyButton @my-event="handleMyEvent"></MyButton>
  </div>
</template>

<script>
  import MyButton from "./MyButton.vue"

  export default {
    methods: {
      handleMyEvent() {
        console.log("my-event was triggered")
      }
    },
    components: {
      MyButton
    }
  }
</script>

Through $emit, we can easily simulate various custom events and check the correctness of the listener to better debug our Vue3 code.

Summary

In Vue3, we can use some practical debugging tool functions to debug Vue3 code more conveniently. Through $refs, we can easily access the DOM elements or subcomponent instances in the component; through $options, we can view all options of the component to better understand the structure and function of the component; through $emit, we can easily Simulate various custom events and check listeners for correctness. These tool functions allow us to better debug Vue3 code and improve our development efficiency.

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