<el-form>
<el-form-item
  :prop="minPrice"
  :rules="{
    required: true,
    validator: PriceValidator,
    trigger: 'blur',
  }"
>
  <el-input type="Number" min="1" v-model="" placeholder="请输入数字"></el-input>
</el-form-item>
</el-form>

// 自定义规则
PriceValidator(rule, value, callback) {
  const reg = /^[1-9]\d{0,8}(\.\d{1,4})?$|^0(\.\d{1,4})?$/ // 正则
  if (reg.test(+value)) {
    callback()
  } else {
    callback(new Error('输入内容应为整数位9位，小数4位'))
  }
},