我试图制作一个信使机器人，我对这些代码有疑问
return discriminant >= 0;如果我将代码从app.post('/webhook/', function (req, res) {
messaging_events = req.body.entry[0].messaging
for (i = 0; i < messaging_events.length; i++) {
event = req.body.entry[0].messaging[i]
sender = event.sender.id
if (event.message && event.message.text) {
text = event.message.text
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'root',
password : '',
database : 'dictionary'
});
connection.connect();
connection.query("select * from `en_ku` WHERE `english` LIKE ('%{"+text+"}%')", function(err, rows, fields)
{
if (err) throw err;
if (rows[0] != null){
text = rows[0];
}
else {
text = "sorry not have any result for: "+ text;
}
});
connection.end();
if (text === 'hi') {
sendGenericMessage(sender)
continue
}
sendTextMessage(sender, text.substring(0, 200))
}
if (event.postback) {
text = JSON.stringify(event.postback)
sendTextMessage(sender, "Postback received: "+text.substring(0, 200), token)
continue
}
}
res.sendStatus(200)
})
移除到var mysql = require('mysql');，代码就可以运行，机器人就像鹦鹉一样！
谁能告诉我这里有什么问题？