Working with PHP 5
Working with PHP 5If you’re about to start learning PHP 5, you may want to know about some of the great features that elevate the latest version of this object-oriented scripting language above the previous version.
PHP has always offered the standard object-oriented toolkit for developers who are familiar with C-like languages such as C++ and Java. These tools enable you to reuse and modify important sections of code without rewriting them.
The new version of PHP includes all the same tools as the last version, but it also features many new functions that make it ideal for developing applications for the Web.
Most developers will be using PHP 5 to create data-driven websites with a database language such as MySQL. The new version of PHP includes many new database functions that make programming a dynamic website easy and efficient.
PHP is the perfect language for creating dynamic, data-driven Web applications because it performs its job on the server side where it can’t be injected with malicious code. It has been one of the most popular scripting languages since the early days of “Web 2.0” because it provides a familiar syntax for C++ and Java developers while enabling programmers to create responsive, dynamic Web pages for a great user experience and you can get yourself trained through online PHP 5 tutorials.
Improved XML Syntax
Working with XML files in PHP 5 is much simpler than in previous versions. Programmers use XML files to store data in software like Active Directory tools, in a tree structure for efficient access during the program’s execution. The new XML tools in PHP 5 are well-integrated and reduce the burden of searching through lists of data for a needed value.
With the updated XML tools, you can simply search through an XML file as you would search through a tree, array, or list. This improvement makes your PHP code much more concise and readable.
Better Error Handling
Another great feature of PHP 5 is its support for exceptions. This improvement makes it more like Java than it was previously. Exceptions provide a way for the runtime environment to automatically check the values of variables. If a variable contains an invalid value, the program will throw an exception. Rather than explicitly checking the value of variables in each function, your code can simply handle exceptions as necessary.
Developing Web Applications
PHP 5 is a general-purpose, open source scripting language specifically designed for the development of Web applications. It can be easily integrated into your HTML pages.
The PHP code that you insert in your Web pages is read by the server host environment. These portions of code that are inserted into your Web pages will enable you to quickly write dynamic Web content, especially if your code is combined with a relational database server such as MySQL.
Using PHP for Web Design
There is a difference between PHP applications and CGI scripts written in languages such as Perl or C. Instead of writing a program with many lines of commands to generate an HTML page, you can write a standard HTML page with PHP code embedded inside it to perform a specific action. The PHP code is embedded between a start tag and an end tag that tell the Web server to go into PHP execution mode.
Some knowledge of HTML coding is strongly recommended for PHP developers. It’s important to understand this framework before coding your first pages in PHP because your program will automatically generate HTML code. Understanding the visual elements you’re creating will help you keep your program lean and efficient.
You should also know that when you insert a small piece of PHP code into an HTML page, you’ll have to change the extension of the file from “.htm” to “.php”. For example, if you have a page named “index.htm” and you insert a line of PHP code, you will have to rename the file to “index.php” before running it.
Combining PHP 5 with HTML
It’s common to mix HTML and PHP instructions within the same Web page. To ensure that your host can locate the correct portions of PHP code, you must indicate the beginning and the end of the PHP snippet to the server.
The marks delimiting these portions of code are called tags. They’re necessary for instructing your server to run PHP code dynamically when a user visits your website. Your PHP code instructions will fall between the start tag and end tag.
Like any good programming language, PHP offers you the possibility to place comments within the code. To create an in-line comment, you begin the line with “//” (two slashes). To create a multi-line comment, begin the section of text with “/*” (slash-asterisk) and end it with “*/” (asterisk-slash).
What distinguishes PHP from languages like JavaScript is that the code is executed by the server. If you have a similar script on your server, the client receives only the result of executing the script. It has no way to access the code that produced this result.
You can even configure your Web server to scan all your HTML files as PHP files. This technique leaves no way for a malicious user to distinguish dynamic pages from static pages.
Your First PHP Program
To get started as a PHP 5 developer, you need two things:
- A text editor for writing your PHP code
- A development environment to test your program
It’s not necessary to install all the elements of your development environment separately. You’ll need to download and install a copy of Apache, PHP, and MySQL for your platform. You can install them all at the same time by downloading a pre-packaged solution such as:
- EasyPHP (Windows)
- WAMP Server (Windows)
- MAMP (Apple)
- BigApache
Safe Coding Practices
The important information to take away from this guide is that, unlike HTML and JavaScript, PHP works on the server side rather than the client side. That means that your PHP code will dynamically generate pages that are readable by the client’s Web browsers. The user’s Web browser will believe that the page it’s displaying was written in HTML. In other words, malicious attacks will be impossible from the client side.
Kidal Delonix is a contributor to Mr. Hoffman's blog. The views and opinions are entirely his/her own and may not reflect Mr Hoffman's views.
