{"id":6918,"date":"2022-08-17T09:53:33","date_gmt":"2022-08-17T07:53:33","guid":{"rendered":"http:\/\/blog.bart.sk\/en\/?p=6918"},"modified":"2022-11-24T14:09:59","modified_gmt":"2022-11-24T13:09:59","slug":"start-developing-php","status":"publish","type":"post","link":"https:\/\/blog.bart.sk\/en\/start-developing-php\/","title":{"rendered":"How to Start Developing in PHP"},"content":{"rendered":"

In the previous article<\/b><\/a> you learned what PHP is and what it’s used for. In this article, we’ll focus on how to get PHP up and running and how to start developing. In simple demonstrations, we’ll show the basic constructions of the language and we’ll also talk about libraries and third-party frameworks.<\/b><\/p>\n

First steps<\/span><\/h2>\n

We need to have PHP installed before we can start writing PHP scripts. Fortunately, PHP is available for every commonly used operating system and web server. On Ubuntu OS we can install PHP using the command <\/span>sudo apt install php<\/span><\/i>. To verify that the installation was successful, we can run the <\/span>php -v<\/span><\/i> command, which should have an output similar to this:<\/span><\/p>\n\n\n\n
\n
PHP <\/span>8.1.8<\/span> (cli) (built: Jul <\/span>11<\/span> 2022<\/span> 08<\/span>:<\/span>29<\/span>:<\/span>57<\/span>) (NTS)<\/span>\r\nCopyright (c) The PHP Group<\/span>\r\nZend Engine v4<\/span>.1.8<\/span>, Copyright (c) Zend Technologies<\/span>\r\n with Zend OPcache v8<\/span>.1.8<\/span>, Copyright (c), by Zend Technologies<\/span><\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
A better way to develop in PHP is to use docker containers. In this way, we’ll be able to work on different projects with different versions of PHP. You can find a sample project using docker, for example, <\/span>here<\/span><\/a>. <\/span><\/p>\n
PHP language basics<\/span><\/h2>\n
If we have PHP installed, we can start programming ? Each PHP script is “delimited” by a tag:<\/span><\/p>\n\n\n\n
\n
<?php<\/b>\r\n\/\/ PHP k\u00f3d<\/span><\/i>\r\n?><\/b><\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
We’ll start with the classic example of “Hello world!”. We create a “hello.php” file with the following content:<\/span><\/p>\n\n\n\n
\n
<?php<\/b>\r\necho<\/span> 'Hello world!'<\/span>;<\/span>\r\n?><\/b><\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
We simply run the script with the command “php hello.php”. The output is as follows:
\n<\/span><\/p>\n
\"PHP<\/p>\n
But in order not to leave you with such a simple example, we’ll show the basic features and constructions of the PHP language. Keywords in PHP are not “case sensitive”, but it’s good to follow certain <\/span>standards<\/span><\/a> for clarity. Each PHP framework may have different standards for how to write code, but the basics are the same.\u00a0<\/span><\/p>\n
PHP variables start with $, can only contain alphanumeric characters, and are created the first time they are assigned a value.<\/b> PHP has weak dynamic typing, which means that the variable type is automatically assigned without declaration. In version 7, however, declarations have been added, and thus we have the possibility to determine the type of the variable. We distinguish local and global scope of variables:<\/span><\/p>\n