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express.js项目中的CORS问题

cors express reactjs node.js

abu abu · 技术社区 · 5 年前

server.js 文件 express.js

const express = require('express');
const bodyParser = require('body-parser');
const addressroute = require('./api/routes/address');
const userroute = require('./api/routes/user');
const mongoose = require('mongoose');
mongoose.set('useCreateIndex', true);
mongoose.connect('mongodb://localhost/addresses', { useNewUrlParser: true });
const db = mongoose.connection;

var cors = require('cors');


let app = express();
app.use(bodyParser.urlencoded( { extended:true } ));
app.use(bodyParser.json());
app.use('/api/address', addressroute);
app.use('/api/users', userroute);
app.use(cors());
app.options('*', cors());
const PORT = process.env.PORT || 4000;
app.listen(PORT);

我安装了CORS npm install cors --save 这是命令。

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://localhost:4000/api/users/register. (Reason: CORS header âAccess-Control-Allow-Originâ missing).[Learn More]
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://localhost:4000/api/users/register. (Reason: CORS request did not succeed).

0 回复 | 直到 5 年前

Matt Carlotta 5 年前

cors 在您的路线上方:

const app = express();
const PORT = process.env.PORT || 4000;

app.use(bodyParser.urlencoded( { extended:true } ));
app.use(bodyParser.json());
app.use(cors());
app.use('/api/address', addressroute);
app.use('/api/users', userroute);
app.listen(PORT);

haMzox 5 年前

请尝试使用以下代码段:

app.all('/*', function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "X-Requested-With");
  next();
});

Ranjith Rana 5 年前

// Try to use the following code   
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();
    });

tomericco 5 年前

你应该把CORS移走( app.use(cors()); )在定义路由之前执行。在这里添加的代码段中,不会对每个请求调用CORS中间件

shradha 5 年前

Cors应该在您的路由之前启用或包含。

const express = require('express');
const cors = require('cors');
const bodyParser = require('body-parser');
const addressroute = require('./api/routes/address');
const userroute = require('./api/routes/user');
const mongoose = require('mongoose');
mongoose.set('useCreateIndex', true);
mongoose.connect('mongodb://localhost/addresses', { useNewUrlParser: true });
const db = mongoose.connection;



let app = express();
app.use(bodyParser.urlencoded( { extended:true } ));
app.use(bodyParser.json());

app.use(cors());

app.use('/api/address', addressroute);
app.use('/api/users', userroute);
const PORT = process.env.PORT || 4000;
app.listen(PORT);

-1

Manish Gowardipe 5 年前

从前端添加调用api时 '访问控制允许来源':'*'