如何在v-textarea Vue.js中更改选定的文本？

<template>
  <div>
    <v-textarea ref="textarea" v-model="content"></v-textarea>
    <button @click="changeSelectedText">更改选定的文本</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      content: ''
    }
  },
  methods: {
    changeSelectedText() {
      const textarea = this.$refs.textarea.$el

      const start = textarea.selectionStart
      const end = textarea.selectionEnd

      const before = this.content.substring(0, start)
      const selected = this.content.substring(start, end)
      const after = this.content.substring(end)

      const newText = '替换的文本'

      this.content = before + newText + after

      // 更新选中文本的起始位置和结束位置
      const newStart = start + newText.length
      const newEnd = newStart
      textarea.setSelectionRange(newStart, newEnd)
    }
  }
}
</script>