关于vue.js:最大3位整数一位小数

<template>  <div class="content">    <input      type="text"      placeholder="请输出数字"      class="input-area"      v-model.trim="tonnage"      maxlength="50"      @input="dealInputVal(tonnage)"    />  </div></template><script>export default {  components: {},  data() {    return {      tonnage: '',    }  },  mounted() {},  methods: {    dealInputVal(num) {      //最大3位整数，一位小数; 100非法，100.1非法，1000不非法，100.11不非法      this.tonnage = num        .replace(/[^\d.]/g, '')        .replace(/\.{1,}/g, '.')        .replace(/^(0(0)+|\.)/g, '')        .replace('.', '$#$')        .replace(/\./g, '')        .replace('$#$', '.')        .replace(/^(-)*(\d+)\.(\d).*$/, '$1$2.$3')      if (parseInt(this.tonnage) >= 1000) {        this.tonnage = '999'      }    }  }}</script><style lang="less" scoped></style>