Javascript MongoDB从body中查找、更新和验证空字段

在更新字段之前，我需要检查以下值是否为空。 因此，我按照以下方式构建，但不检索msg错误，也不允许我向配置文件用户升级

router.post("/profileEdit/:id", ensureAuthenticated, (req, res) => {
  var id = mongoose.Types.ObjectId(req.params.id);
  let errors = [];
  if (!req.body.firstName) {
    errors.push({ text: "Please add your first name" });
  }
  if (!req.body.lastName) {
    errors.push({ text: "Please add your last name" });
  }
  if (!req.body.username) {
    errors.push({ text: "Please add your username" });
  }
  if (!req.body.email) {
    errors.push({ text: "Please add you email" });
  }

  if (errors.length > 0) {
    res.render("users/profileEdit", {
      errors: errors,
      firstName: req.body.firstName,
      lastName: req.body.lastName,
      username: req.body.username,
      email: req.body.email
    });
  } else {
    User.updateOne(
      { _id: id },
      {
        $set: {
          firstName: req.body.firstName,
          lastName: req.body.lastName,
          username: req.body.username,
          email: req.body.email
        }
      }
    ).then(user => {
      req.flash("success_msg", "Profile Updated");
      res.redirect("/users/profile/" + id);
    });
  }
});

---

如何验证每个字段的req.body是否为空？在验证之后，我需要更新mongodb内部的信息。

解决方案如下：

在执行其他操作之前，我只需要找到_id:id，这样，由于上面的字段是空的，应用程序将返回相同的页面并填充字段

router.post("/profileEdit/:id", ensureAuthenticated, (req, res) => {
  var id = mongoose.Types.ObjectId(req.params.id);
  let errors = [];

  if (!req.body.firstName) {
    errors.push({ text: "Please add your first name" });
  }
  if (!req.body.lastName) {
    errors.push({ text: "Please add your last name" });
  }
  if (!req.body.username) {
    errors.push({ text: "Please add your username" });
  }
  if (!req.body.email) {
    errors.push({ text: "Please add you email" });
  }

  if (errors.length > 0) {
    User.find(
      { _id: id },
      {
        firstName: 1,
        lastName: 1,
        username: 1,
        email: 1,
        password: 1,
        _id: { $elemMatch: { _id: id } },
        date: 1
      }
    ).then(user => {
      res.render("users/profileEdit", {
        user: user
      });
    });
  } else {
    User.updateOne(
      { _id: id },
      {
        $set: {
          firstName: req.body.firstName,
          lastName: req.body.lastName,
          username: req.body.username,
          email: req.body.email
        }
      }
    ).then(user => {
      req.flash("success_msg", "Profile Updated");
      res.redirect("/users/profile/" + id);
    });
  }
});

---

那么，什么不起作用呢？@Carlos Orelhas：虽然你可以用js来做，但在node.js的世界里，使用它是很常见的，看看它可能会对你有所帮助。@technophyle我上面展示的方式是行不通的。。无法验证字段验证代码在我看来很好。可能是您的

profileEdit

模板有问题。两者都可以正常工作，但我认为我需要首先找到id，然后进行验证。。由于这种方式，请在profileEdit中显示多行