javascript - Node.js 无法读取未定义的属性“名字”

Question

我是 node.js 的新手。我正在尝试创建一个注册页面并使用 mysql 将输入的值保存在数据库中。

我可以通过在请求 header 上传递参数来做到这一点。但是，在请求 header 中传递参数始终不是一个好主意。所以尝试在请求体上传递参数。

我正在使用 Postman 来测试我的 node.js 服务。

这是我的演示应用程序的 github 链接

https://github.com/debasish283/node_gulp

我还需要做什么才能在请求正文中传递参数？

在请求正文中传递参数时出现以下错误。

TypeError: Cannot read property 'firstname' of undefined
   at Object.db.register (/var/projects/node_gulp/server/db.js:13:65)
   at wrapper.register (/var/projects/node_gulp/server/wrapper.js:8:12)
   at Layer.handle [as handle_request] (/var/projects/node_gulp/node_modules/express/lib/router/layer.js:95:5)
   at next (/var/projects/node_gulp/node_modules/express/lib/router/route.js:131:13)
   at Route.dispatch (/var/projects/node_gulp/node_modules/express/lib/router/route.js:112:3)
   at Layer.handle [as handle_request] (/var/projects/node_gulp/node_modules/express/lib/router/layer.js:95:5)
   at /var/projects/node_gulp/node_modules/express/lib/router/index.js:277:22
   at Function.process_params (/var/projects/node_gulp/node_modules/express/lib/router/index.js:330:12)
   at next (/var/projects/node_gulp/node_modules/express/lib/router/index.js:271:10)
   at Function.handle (/var/projects/node_gulp/node_modules/express/lib/router/index.js:176:3)

代码: 服务器 -> wrapper.js

var express = require('express');
var db = require('./db.js');
var config = require('config');

var wrapper = {
register: function(req, res) {
console.log('inside wrapper');
db.register(req.body);
}
};
module.exports = wrapper;

路由 -> index.js

var router = require('express').Router();
var wrapper = require('../server/wrapper');

router.post('/register', wrapper.register);

module.exports = router;

app.js

var express = require('express');
var app = express();
var port = process.env.PORT || 3000;
var router = require('./routes');
var bodyParser = require('body-parser');

app.use('/', router);

app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

app.listen(port, function() {
console.log('Server started at ' + port);
});

服务器-> db.js

var mysql = require('mysql');
var config = require('config');

var connection = mysql.createConnection({
host: config.get('database.host'),
user: config.get('database.user'),
password: config.get('database.password'),
database: config.get('database.database')
});
var db = {
register: function(parameter) {
var qry = 'insert into users values (' + "'" + parameter.firstname + "'" + ',' + "'" + parameter.lastname + "'" + ',' + "'" + parameter.username + "'" + ',' + "'" + parameter.bday + "'" + ',' + "'" + parameter.gender + "'" + ',' + "'" + parameter.password + "'" + ')';
console.log(qry);
connection.connect();
connection.query(qry, function(err, rows, fields) {
if (!err) {
        console.log('The solution is: ', rows);
        } else
            console.log('Error while performing Query.' + err);
    });

    connection.end();
}
};
module.exports = db;

Answer 1

您需要在路由之前移动您的主体解析中间件，以便在执行您的路由处理程序之前首先解析请求主体:

// app.js

// ...

app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

app.use('/', router);

// ...