Question

我正在制作带有登录屏幕等的基本网站。

目前，我正在注册页面上，该页面对用户的验证很少，例如“电子邮件存在”，“确认电子邮件已发送”等。

实现此目的或您个人喜好的最佳方法是什么？

下面，我将代码包含在我尝试实现此方法的示例中。

我具有从服务器端到控制台的基本日志记录，其中包含以下代码段。

app.post("/register-email", async (req, response) => {
  let emailAvailabilitylResponse = "";
  var Email = req.body.email;
  await sql.connect(config);
  var request = new sql.Request();

  request.input("Email", sql.VarChar, Email);
  const result = await request.execute("dbo.CheckEmailExists");

  if (result.recordsets[0].length > 0) {
    emailAvailabilitylResponse = "This email already exists"; // this works on console
    console.info(emailAvailabilitylResponse);
    console.log(req.body);
  } else {
    console.log({ Email });
    emailAvailabilitylResponse = "An email has been sent to your inbox"; //this work on console
console.info(emailAvailabilitylResponse);

    const token = jwt.sign({ user: Email }, "register-email", {
      expiresIn: 3600000
    });

    response.status(200).json({
      ok: true,
      user: Email,
      jwt: token,
      emailAvailability: emailAvailabilityResponse
    });

我试图将此信息传递回我的json文件中，但是当尝试向用户显示此信息时仍然无法正常工作。

这是我的代码的客户端。这是一个句柄提交，一旦单击注册表的按钮，就会触发该提交。


  handleSubmit(e) {
    e.preventDefault();
    const EmailAvailbiltly = "";

    if (this.state.email.length < 8) {
      alert(`please enter email correctly `);   //this works and displays as alert
    } else {
      const data = { email: this.state.email };
      console.log(data);

      fetch("/register-email", {
        method: "POST", // or 'PUT'
        headers: {
          Accept: "application/json,",
          "Content-Type": "application/json"
        },
        body: JSON.stringify(data)
      })
        .then(response => {
          console.log("response before it is broken down " + response);

          return response.json();
        })
        .then(({ jwt, user, emailAvailabilityResponse }) => {
          console.log(
            "After it is broken down",
            jwt,
            user,
            emailAvailabilityResponse
          );
          EmailAvailbiltly = emailAvailabilityResponse;
        });

      alert(`"reponse 2" ${EmailAvailbiltly}`);         // I cannot get the an alert with this response. 
      console.log(EmailAvailbiltly);                    //This should be  the messages contained in                                                   
                                                        //server.js 
      console.log(`"reponse 2" ${EmailAvailbiltly}`);
    }
  }

编辑

根据请求的控制台信息

如果存在电子邮件


[0] Server running on port 5000
[0] This email already exists
[0] { email: 'testuser@gmail.com' }

如果电子邮件不存在


[0] { Email: 'testing@gmail.com' }
[0] An email has been sent to your inbox

但这是纯粹的控制台，而我希望它可以是前端

Answer 1

为解决这个问题，我在两个if语句中创建了一条错误消息，并将其与json一起传递回去。之后，我只是从前端调用了错误消息。

伪代码

error message 

if(a statement)
error message = "whatever it needs to be"
res.sendjson(with error message)

else(a statement)
error message = "something different"
res.sendjson(with error message)

然后在我的客户端，我只是提取了错误消息，然后将其放入警报中。

我希望这对某人有帮助:)

从服务器到客户端的输入验证

1 个答案: