为什么我在 UI 中没有收到验证 Flash 消息，我收到 flash 错误，如下所示 [object Object],[object Object],[object Object]

Question

我正在开发 NodeJs 应用程序，它是博客应用程序。 and i used express Validator,i am trying to validateData with flash message before save posts in database with express flash message in UI side, i successfully save data in database but message is not appear in UI side after submitting forms I gets flash error like this [object Object],[object Object],[object Object]

我正在使用哈巴狗模板引擎。

应用程序.js

const express = require("express");
const path = require("path");
const app = express();
const mongoose = require("mongoose");
const Article = require("./models/article");
const bodyParser = require("body-parser");
const { check, validationResult } = require("express-validator");
const flash = require("connect-flash");
const session = require("express-session");

//Express Session Middleware
app.use(
  session({
    secret: "keyboard cat",
    resave: true,
    saveUninitialized: true
  })
);
app.use(flash());

app.use((req, res, next) => {
  res.locals.errors = req.flash("error");
  res.locals.successes = req.flash("success");
  next();
});
app.get("/articles/add", (req, res) => {
  res.render("add_articles", {
    title: "Add Articles"
  });
});

// Add Submit POST Route
app.post(
  "/articles/add",
  [
    check("title", "Title is required")
      .not()
      .isEmpty(),
    check("author", "Author is required")
      .not()
      .isEmpty(),
    check("body", "Body is required")
      .not()
      .isEmpty()
  ],
  (req, res) => {
    const errors = validationResult(req);

     if (errors) {
      res.render("add_articles", {
        title: "Add Articles",
        errors: errors
      }); 
    } else {
      //GetErrors
      let article = new Article();
      article.title = req.body.title;
      article.author = req.body.author;
      article.body = req.body.body;

      article.save(err => {
        if (err) {
          console.log(err);
          return;
        } else {
          req.flash("success", "Article Added");
          res.redirect("/");
        }
      });
    }
  }
);

消息.pug

.messages
 each type in Object.keys(messages)
    each message in messages[type]
      div(class="alert alert-"+type) #{message}
   

布局.pug

 .container
      if successes
        for success in successes
           div.alert.alert-success #{ success }
      if errors
        for error , i in errors
           div.alert.alert-danger #{ error }

任何帮助都非常感谢..

Answer 1

1) 我要注意的第一件事是关于您检查是否存在任何验证错误的方式：

const errors = validationResult(req); if (errors) {...}

应替换为：

const errors = validationResult(req); if (errors.isEmpty()) {...}

2）还有另一个问题，与获取错误数组有关。 代替：

res.render("add_articles", { title: "Add Articles", errors: errors });

你需要使用：

res.render("add_articles", { title: "Add Articles", errors: errors.array() });

来源： Express 验证器文档