限制输入emoji表情包

<van-field
  v-model.trim="form.orgPark"
  name="orgPark"
  @input="onInput($event, 'orgPark')"
/>

export default {
  methods: {
    onInput(text, keyname) {
      var patt = /[\uD800-\uDBFF][\uDC00-\uDFFF]/g
      this.form[keyname] = text.replace(patt, function(char) {
        if (char.length === 2) {
          return ''
        } else {
          return char
        }
      })
    },
  }
}