Opencart objects defined, Opencart development tutorials

Predefined objects’ methods are functionalities which are already defined and you can use it directly.


It prevents from DRY, which means Don't Repeat Yourself. Don’t write code unless you have to. Write code only what you need, if you missed these predefined objects’ methods then you may repeat codes.


You can find predefined objects’ methods at system/library


Opencart has many predefined objects’ methods that can be called in Controller and Model.  Like in admin section we can see predefined objects like: config, log, event, load, request, response, db, session, cache, url, langauge, openbay, document, customer, currency, tax, weight, length, cart, encryption, model_setting_event, user.



Database Object of Opencart is
$this->db

Methods are:

• $this->db->escape($value) - mysql_real_escape_string() on the value passed
• $this->db->countAffected() - rows affected by an UPDATE query
• $this->db->getLastId() - last auto increment id same as mysql_insert_id()
• $this->db->connected() – Pings a server connection, or tries to reconnect if the connection has gone down

$this->db->query($sql)
All SQL queries are run from $this->db->query method which looks like: $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "category WHERE $this->db->query("REPLACE INTO `" . DB_PREFIX . "category_path` SET ...); $this->db->query("INSERT INTO `" . DB_PREFIX . "category_path` SET ...); $this->db->query("DELETE FROM " . DB_PREFIX . "category WHERE ...); $this->db->query("UPDATE " . DB_PREFIX . "category SET image = ...);

$this->db->query method returns three properties:  
$result->num_rows = $query->num_rows; - gets the number of rows in a results  
$result->row = isset($data[0]) ? $data[0] : array(); - get the first row data  
$result->rows = $data; - get an array of row results

Installing OpenCart Vesrion 3.0.2.0 - Opencart Development tutorials Video 2

•  Download OpenCart files from http://opencart.com 
• Create a database
• Upload files and folders
• Create config files one at root folder and another inside admin/ folder. 
• Steps to create custom URL to work locally https://webocreation.com/blog/steps-create-custom-url-work-locally-xampp-localhost-virtual-host
• Go to the URL
• If you see any other errors then you have to solve them. One could curl disabled which you have to enable from php.ini
• Delete the install folder, if you rename the folder then you are a by-passing error message but there will be security holes remained in that folder so the hacker can find it easily and exploit your database so strongly recommended to delete the install folder after installation is complete.