问一下 为什么要get两次才能res.send正确的结果

[王紫川]

var express = require('express'); //引入express模块
var mysql = require('mysql'); //引入mysql模块

var fs = require('fs');
var URL = require('url');
var app = express(); //创建express的实例
var bodyParser = require('body-parser');
//const bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
var connection = mysql.createConnection({ //创建mysql实例
host: '192.168.48.128',
port: '3306',
user: 'root',
password: 'password',
database: 'mydb'
});
connection.connect();
// 下面是解决跨域请求问题
app.all('*', function (req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "X-Requested-With");
res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");
res.header("X-Powered-By", ' 3.2.1');
res.header("Content-Type", "application/json;charset=utf-8");
next();
});
var sql = 'SELECT * FROM goods';
var text=" ";
connection.query(sql, function (err, result) {
if (err) {
console.log('[SELECT ERROR]:', err.message);
}
text = JSON.stringify(result);
console.log(result); //数据库查询结果返回到result中

});
//connection.destroy();
var router = express.Router();
router.get('/', function (req, res,next ) {

res.send('welcome');
//res.sendStatus(200);
});
var temp = " ";

router.get('/read', function (req, res, next) {
var params = URL.parse(req.url, true).query;
//connection.connect();
connection.query('select * from goods where id=' + params.id +';', function (err, result,next ) {

if (err) {
console.log('[SELECT ERROR]:', err.message);
} temp = JSON.stringify(result);
console.log(temp); //数据库查询结果返回到result中
});
res.send(temp);
//res.sendStatus(200);
//connection.destroy();
});
router.get('/h', function (req, res) {
res.send("h");
});
router.get('/G', function (req, res) {
res.send("G");
});
app.use('/', router);
//connection.end();
app.listen(1337, function () {
//监听3000端口
console.log('Server running at 1337 port');
});