Vuejs :如何在V-model中不使用布尔值？

<input type="checkbox" v-model="selectedValue">

data() {
  return {
    selectedValue: 'checked'
  }
}

<input type="checkbox" v-model="selectedValue">

data() {
  return {
    selectedValue: 1
  }
}

<input type="checkbox" value="value1" v-model="selectedValues">
<input type="checkbox" value="value2" v-model="selectedValues">
<input type="checkbox" value="value3" v-model="selectedValues">

data() {
  return {
    selectedValues: []
  }
}

<input type="radio" value="value1" v-model="selectedValue">
<input type="radio" value="value2" v-model="selectedValue">
<input type="radio" value="value3" v-model="selectedValue">

data() {
  return {
    selectedValue: null
  }
}