当表单的属性为数组时，该怎么校验数组元素的每一项呢？

效果图：

vue 代码

<template>
  <div style="width: 500px">
    <el-form
      :model="ruleForm"
      :rules="rules"
      label-width="100px"
      ref="ruleForm"
    >
      <el-form-item label="书籍推荐" prop="bookRecList">
        <div style="display: flex; margin-bottom: 10px">
          <el-button type="primary" @click="ruleForm.bookRecList.push('')">添加书籍</el-button>
        </div>
      </el-form-item>
       <div v-for="(item, index) in ruleForm.bookRecList" :key="index">
        <!-- rules也可以直接赋值规则, 如：
          :rules="[
            { required: true, message: '书籍名称不能为空', trigger: 'change' },
            { min: 1, max: 10, message: '长度在 1 到 10 个字符', trigger: 'change'}
            ]"
         -->
         
          <el-form-item :prop="`bookRecList[${index}]`" :rules="rules.book">
            <el-input
              placeholder="请输入内容"
              v-model="ruleForm.bookRecList[index]"
            >
              <span slot="suffix"> {{ item.length }}/10 </span>
            </el-input>
          </el-form-item>
        </div>
    </el-form>
  </div>
</template>

<script>
export default {
  data() {
    const validBookRecList = (rule, value, callback) => {
      if (value.length < 1) {
        callback(new Error("至少推荐一个书籍"));
      } else {
        callback();
      }
    };
    const validBook = (rule, value, callback) => {
      console.log(rule);
      if (value === "" || value === null) {
        callback(new Error("请输入书籍名称"));
      } else {
        if (value.length > 10) {
          callback(new Error("书籍名称长度不超过10"));
        }
        callback();
      }
    };
    return {
      ruleForm: {
        bookRecList: [""],
      },
      rules: {
        bookRecList: { validator: validBookRecList, trigger: "change" },
        book: { validator: validBook, trigger: "change" },
      },
    };
  },
};
</script>