naive-ui/demo/documentation/components/select/enUS/fallbackOption.md

# Fallback Option
In some rare cases, you may fill the value but not the corresponding options. For example in async cases, or simply you passed a bad value. If you want to control the way of the value to be displayed, use `fallback-option` prop to control how to create a option using the value.

If you don't need fallback options, simply set it to `false`. Now only the value appeared in the options will be viewed as a valid value. Invalid values will be cleared in the operations of the component.
```html
<n-select
  v-model="singleValue"
  :options="options"
/>
<n-select
  v-model="multipleValue"
  multiple
  :fallback-option="trim"
  :options="options"
/>
<n-select
  v-model="singleValue"
  placeholder="No Fallback"
  :fallback-option="false"
  :options="options"
/>
<n-select
  v-model="multipleValue"
  placeholder="No Fallback"
  multiple
  :fallback-option="false"
  :options="options"
/>
```
```js
export default {
  data () {
    return {
      trim (value) {
        return {
          label: value.split(' ')[0],
          value
        }
      },
      singleValue: 'A Nowhere Value',
      multipleValue: ['First Nowhere Value', 'Second Nowhere Value'],
      options: [
        {
          label: "Everybody's Got Something to Hide Except Me and My Monkey",
          value: 'song0',
          disabled: true
        },
        {
          label: 'Drive My Car',
          value: 'song1'
        },
        {
          label: 'Norwegian Wood',
          value: 'song2'
        },
        {
          label: 'You Won\'t See',
          value: 'song3',
          disabled: true
        },
        {
          label: 'Nowhere Man',
          value: 'song4'
        },
        {
          label: 'Think For Yourself',
          value: 'song5'
        },
        {
          label: 'The Word',
          value: 'song6'
        },
        {
          label: 'Michelle',
          value: 'song7',
          disabled: true
        },
        {
          label: 'What goes on',
          value: 'song8'
        },
        {
          label: 'Girl',
          value: 'song9'
        },
        {
          label: 'I\'m looking through you',
          value: 'song10'
        },
        {
          label: 'In My Life',
          value: 'song11'
        },
        {
          label: 'Wait',
          value: 'song12'
        }
      ]
    }
  }
}
```
```css
.n-select {
  width: 180px;
  margin: 0 12px 8px 0;
}
```