错误：全局连接已经存在。 首先调用sql.close（）

您好我正在创build节点js restful api通过使用sqlserver数据库，我准备得到api时，我使用的API输出显示为JSON格式，而刷新浏览器获得其显示“错误：全局连接已经存在调用sql.close ）先。“错误。 我正在添加代码

var express = require("express"); var sql = require("mssql"); var app = express(); //Initiallising connection string var dbConfig = { user: 'sa', password: 'India123', server: 'localhost', database: 'sample' }; app.get('/login', function (req, res) { // connect to your database var data = { "user": "" }; sql.connect(dbConfig, function (err) { if (err) console.log(err); var request = new sql.Request(); request.query('select * from Login', function (err, result) { if (err) console.log(err) // send data as a response //res.send(result.recordset); data["user"] = result.recordset; res.send(data); }); }); }); var server = app.listen(5000, function () { console.log('Server is running..'); }); 

请纠正我的代码。 感谢提前

Answer 1

 // db.js var mssql = require("mssql"); var dbConfig = { user: 'sa', password: 'India123', server: 'localhost', database: 'sample' }; var connection = mssql.connect(dbConfig, function (err) { if (err) throw err; }); module.exports = connection; // app.js var db = require("db"); var express = require("express"); var app = express(); app.get('/login', function (req, res, next) { var request = new db.Request(); request.query('select * from Login', function (err, result) { if (err) return next(err); var data = {}; data["user"] = result.recordset; res.send(data); }); }); var server = app.listen(5000, function () { console.log('Server is running..'); });