如何将数据从html发送到节点js？

Posted 2023-03-07

【中文标题】如何将数据从html发送到节点js？

【英文标题】：how to send data from html to node js?

【发布时间】：2021-08-22 09:59:00

【问题描述】：

下面是我的html 代码，我从那里通过 JQuery 发送数据

 <script type="text/javascript">
      $(document).ready(function()
        sndt();
        function sndt(nid)
        $.ajax(
          url:"localhost:3000/client",
          method:"POST",
          data:nid,test:"dooo",
          success:function(data)
              $("#video").html(data);
      ,
      error:function(data)
        console.log("ZUBAIR");
      
        )
      
      )
</script>

现在我想在我的节点 js 控制台中显示这个测试数据这是我在节点 js 中的代码

require("dotenv").config();
const express = require("express");
const path = require("path");
var cons = require('consolidate'); 
var bodyParser = require('body-parser');
const app = express();
app.use(function(req, res, next) 
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  next();
);
app.use(bodyParser.urlencoded(extended:false));
app.engine('html', cons.swig)
app.set('views', path.join(__dirname, 'www'));
app.set('view engine', 'html');

var PORT = process.env.PORT || 3000; // signalingServerPort
var localHost = "http://localhost:" + PORT; // http
app.use(express.static(path.join(__dirname, "www")));
// Remove trailing slashes in url
app.use(function (req, res, next) 
  if (req.path.substr(-1) === "/" && req.path.length > 1) 
    let query = req.url.slice(req.path.length);
    res.redirect(301, req.path.slice(0, -1) + query);
   else 
    next();
  
);
// no room name specified to join
app.get("/join/", function (req, res) 
  res.redirect("/");
);
// join to room
app.post("/join/*", function (req, res) 
  var t = (req.body.test);
  console.log("ttttt"+ t);
  if (Object.keys(req.query).length > 0) 
    console.log("redirect:" + req.url + " to " + url.parse(req.url).pathname);
    res.redirect(url.parse(req.url).pathname);
   else 
    var t = (req.body.test);
  console.log("ttttt"+ t);
    res.sendFile(path.join(__dirname, "www/client.html"));
  
);

这些是我面临的错误

Access to XMLHttpRequest at 'localhost:3000/client' from origin 'http://localhost:3000' has been blocked by CORS policy: Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, chrome-untrusted, https.

和

jquery-2.2.4.js:9175 POST localhost:3000/client net::ERR_FAILED

这是我的节点 js 代码，我哪里出错了？？谢谢？

【参考方案1】：

当你从前端调用到后端时，这是一个 cors 问题，你必须在后端代码中启用 cors

所以你需要先通过运行以下命令来安装cors

npm install cors

安装后进入node js代码并导入cors并使用cors，因为我使用了以下代码

  var cors = require('cors')
        var app = express()
        
        app.use(cors())

【讨论】：

Access to XMLHttpRequest at 'localhost:3000?uuu=43683CleanCake' from origin 'http://localhost:3000' has been blocked by CORS policy: Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, chrome-untrusted, https.

请指导我这个jquery-2.2.4.js:9175 POST localhost:3000/client net::ERR_FAILED为什么我收到这个错误