先看效果

代码如下

父组件

<template>
  <ChildForm ref="childFormRef" />
  <button @click="validateForm">校验表单</button>
</template>
<script setup>
import { ref } from 'vue';
import ChildForm from './ChildForm.vue';
const childFormRef = ref(null);
const validateForm = async () => {
  if (childFormRef.value) {
    try {
      const isValid = await childFormRef.value.validate();
      console.log('Form valid:', isValid);
    } catch (error) {
      console.error('Validation error:', error);
    }
  }
};
</script>

子组件

<!-- ChildForm.vue -->
<template>
    <van-form ref="formRef">
      <!-- 表单项 -->
      <van-field label="账号" name="账号" v-model="pageList.fieldValue" :rules="rules" />
      <van-field
      v-model="pageList.password"
      label="密码"
      name="密码"
      type="password"
      placeholder="请输入密码"
      :rules="[{ required: true, message: '请输入密码' }]"
    />
    </van-form>
  </template>
  <script setup>
  import { ref, defineExpose } from 'vue';
  const formRef = ref(null);
  let pageList = ref({
    fieldValue:'',
    password:'',
  })
  const rules = ref([
    { required: true, message: 'This field is required' }
  ]);
  
  const validate = async () => {
    if (formRef.value) {
      try {
        await formRef.value.validate();
        return true;
      } catch (error) {
        return false;
      }
    }
    return false;
  };
  defineExpose({ validate });
  </script>
  

父组件通过ref获取子组件的引用，在父组件的点击事件中调用子组件的validate方法进行表单验证，如果验证通过则执行提交逻辑。子组件通过defineExpose暴露其validate方法给父组件使用。这样父组件就可以通过childForm.value.validate调用子组件的验证方法了。