<button type="button" @click="greet">count is {{ count }}</button>

function greet(event) {
  if (event) {
    console.log(event)
    console.log(event.target)
    console.log(event.target.tagName)
  }
}

很明显没传参数，但是获取到了相应的值

<input type="text" @change="handleChange" />

function handleChange(event) {
  console.log(event)
  console.log(event.target)
  console.log(event.target.value)
}

在vue3中

    <Input ref="test" @input="geet"></Input>

const test = ref()
const geet = () => {
  console.log(test)
  console.log(test.value)
  console.log(test.value.value)
  console.log(test.value.offsetHeight)
}