How To Get a List of Databases from MySQL Servers? - MySQL FAQs - PHP Connections and Query Execution

Once you got a MySQL server connection object successfully, you need to know what databases are available on the server and which database you should use to manage your tables and data. To get a list of all available databases on your MySQL server, you can use the mysql_list_dbs() function. Note mysql_list_dbs() will not return an array of database names. It returns a result object, which requires mysql_fetch_object() call to loop through each database object.

The tutorial exercise below shows you a good example of how to get a list of databases as a result object. Then "while" loop is used to fetch each database object from the result object. Finally, an object property "$obj->Database" is used to get the database name:

<?php
  $con = mysql_connect('localhost:8888', 'dev', 'iyf');
  print("List of databases:\n");
  $res = mysql_list_dbs($con);
  while ($obj = mysql_fetch_object($res)) {
     print($obj->Database . "\n");
  }
  mysql_close($con); 
?>

If you run this script, you will get something like this:

List of databases:
information_schema
mysql
test