vee-验证3.x。验证“如果只有另一个值为空，则需要值”

import { createApp } from 'vue';
import { createI18n } from 'vue-i18n';
import { createRouter, createWebHistory } from 'vue-router';
import { createForm, configure } from 'vee-validate';
import { required, confirmed } from '@vee-validate/rules';

// 引入语言包
import zhCN from '@vee-validate/i18n/dist/locale/zh_CN.json';

// 添加验证规则
configure({
  generateMessage: createI18n().global.t,
});

createForm();

// 添加中文语言包
createI18n({
  locale: 'zh_CN',
  messages: {
    zh_CN: zhCN,
  },
});

// 创建Vue应用
const app = createApp(App);

// 添加路由
const router = createRouter({
  history: createWebHistory(),
  routes,
});

app.use(router);
app.use(createI18n());

app.mount('#app');

<template>
  <form @submit="submitForm">
    <div>
      <label for="value1">值1：</label>
      <input v-model="value1" type="text" name="value1" v-validate="'required_if:value2,''" />
      <span>{{ errors.value1 }}</span>
    </div>
    <div>
      <label for="value2">值2：</label>
      <input v-model="value2" type="text" name="value2" v-validate="'required_if:value1,''" />
      <span>{{ errors.value2 }}</span>
    </div>
    <button type="submit">提交</button>
  </form>
</template>

<script>
export default {
  data() {
    return {
      value1: '',
      value2: '',
    };
  },
  methods: {
    submitForm() {
      // 表单提交逻辑
    },
  },
};
</script>

<span>{{ errors.value1 }}</span>
<span>{{ errors.value2 }}</span>