如何为我的网站应用程序编写MySQL DB单连接字符串

I have a website built using HTML,JS,PHP. I use Linux OS and apache2 server and MySQL as a back end. To connect to the MySQL server I have created connection in each PHP page,But I want this connection string to be written in a single file(Like web.config in Visual studio),so that I can change the connection string easily whenever it is necessary.I have installed PHPMYADMIN and I can see couple of config files in that folder.But I do not know where I need to write this connection string?

Or shall I create a PHP file with the connection string and include() this file in every other PHP files and create the instance of the connection?

I am not using any IDE for building the website.

Any help is greatly appreciated.

Thanks a lot.

Create a PHP file where you connect to the SQL server and save the connection in a variable. Include this file everywhere you need the connection.

Pseudo example

init.php

$db_connection = connect_to_db($server, $username, $password, $db);

other_files.php

include "init.php";
execute_query("query", $db_connection);

Create a PHP file with connection setting and just include it in all pages at the top.

http://php.net/manual/en/pdo.connections.php Here is an exampe with PDO Just put that in a php file and include it where is needed.