function submitForm1() {
   //RefChilde.value.selectOption 为自组件的数组对象
  if (!RefChilde.value.selectOption) {
    proxy.$modal.msgWarning("请选择一条信息。");
    return;
  form.value.exSubjectId = RefChilde.value.selectOption
    .map((item) => item.id)
    .join(",");
  form.value.exSubjectTitle = RefChilde.value.selectOption
    .map((item) => item.exTitle)
    .join(",");
  open1.value = false;
}


后端java实现
list.stream().map(TaskBusiness::getReceivePersonId).collect(Collectors.joining(","))