, PHP questions about database connection errors

For help, PHP has just migrated the website about database connection errors and checked the index of the root directory. php displays the database connection file code // database class require_once ('class/dbconfig. php '); require_once ('class/class_user.php'); r help, PHP database connection error
After migrating the website, I checked the index. php in the root directory to display the database connection file code.
// Database class
Require_once ('class/dbconfig. php ');
Require_once ('class/class_user.php ');
Require_once ('class/class_public.php ');
Require_once ('class/class_shop.php ');

Open the class/dbconfig. php file. the code is

PHP code

  Class dbconfig {// connect to the database function con () {$ con = mysql_connect ('2017. 0.0.1 ', 'root', '123'); mysql_select_db ("database_591", $ con); return $ con;} // run the SQL function getRs ($ SQL, $ con) {mysql_query ('set names utf8'); return mysql_query ($ SQL, $ con);} // run the SQL statement without returning the function deff_getRs ($ SQL, $ con) {mysql_unbuffered_query ('set names utf8'); return mysql_unbuffered_query ($ SQL, $ con);} // Close the dataset function c LearRS ($ rs) {mysql_free_result ($ rs);} // closes the database function clearDB ($ con) {mysql_close ($ con );} // function rsRows ($ rs) {return mysql_num_rows ($ rs);} // dataset pointer function rsSeek ($ rs, $ n = 0) {return mysql_data_seek ($ rs, $ n) ;}}$ db = new dbconfig;?>

Only 123456 is changed to your database password.

But I still cannot connect to the database website. I cannot open other related database files, and I can't change it or I can't. what's the problem? new to PHP? thank you for your advice.

------ Solution --------------------
The directory name is _ 519.
Then the database name is _ 519.

Mysql_select_db ("_ 591", $ con );