Question

当用户登录系统时，我是从前端获取数据库名称的，我必须与该数据库建立连接以进行进一步的处理。如果在同一页面上创建连接，我可以做到这一点，但我想使用'exports' 我正在尝试这个。我是node.js的新手，所以如果有一些非常愚蠢的错误，请不要介意并帮助我理解。我尝试了其他导出方式，但无法使其运行。

我的DB_dynamic.js：

var mysql = require('mysql');
exports.dynamicConnection= function(dbname){
var connection = mysql.createConnection({
  host: process.env.DBHost || 'localhost',
  port: process.env.DBPort || 3306,
  user: process.env.DBUser || 'root',
  password: process.env.DBPassword || '',
  database: process.env.DBName || dbname
});
connection.connect((err) =>{
  if(err) throw err;
  console.log('Mysql Connected...');
});
}

现在在我的model.js中

var new_conn = require('./DB_dynamic.js');
var conn = new_conn.dynamicConnection(dbname);
  conn.query("my query"); //Error!

错误：

TypeError: Cannot read property 'query' of undefined

Answer 1

DB_dynamic.js

const mysql = require('mysql');


module.exports = dbConnection = (dbname) => {
    return connection = mysql.createConnection({
        host: process.env.DBHost || 'localhost',
        port: process.env.DBPort || 3306,
        user: process.env.DBUser || 'root',
        password: process.env.DBPassword || '',
        database: process.env.DBName || dbname
    });
};

model.js

let dbConnection = require('./DB_dynamic.js');

console.log(dbConnection("your_db_name").query("your_query"))

Answer 2

module。exports.dynamicConnection = function（dbname）{

使用导出与动态数据库node.js连接

2 个答案: