Difference between revisions of "PHP"

Revision as of 23:38, April 1, 2008

PHP is a server-side scripting language for creating interactive web pages. The acronym PHP derives from Personal Home Page, but now it is defined as "PHP: Hypertext Pre-Processor" (it means "something to handle data before it becomes HTML" ^[1] ). Unlike HTML, JavaScript and others, PHP is a Server-Side scripting language. It most always is processed into HTML for use in a web page.

PHP is one of the most popular scripting languages in the Open Source world, which is often used together with Apache on Linux or on other paid platforms such as Microsoft IIS on Windows.

The PHP syntax is very similar to Perl and C. [1]

PHP is an interpreted language (like Perl) and not a compiled one (like Java or C).

String handling

The string concatenation operator is the period (or full stop). This is a big difference from most other languages, which use a plus sign or ampersand.

Example:

 $first = "car";
 $second = "nation";
 $product= $first . $second;

 // Equivalent to:
 $product= "carnation"

PHP recognizes variable names within strings which are enclosed in double quotes. Since all variables begin with a dollar sign, it is easy to embed one string inside another. This is the preferred way to create HTML output.

For example:

   $first = "John";
   $middle = "Quincy"
   $last = "Adams";
   
   // Show full name, in bold format
   echo "<B>$first $middle $last</B>";

This outputs "<B>John Quincy Adams</B>" to the HTML page.

Databases

PHP is compatible with multiple databases, MySQL being the most popular. They go together so well that it's tempting to think of PHP as primarily middleware to link MySQL on the back end to HTML on the front end.

Overall, PHP is compatible with:

• MySQL
• PostgreSQL
• MS-SQL 2000
• Oracle

and many others.

Books

• How to Do Everything with PHP & MySQL, Vikram Vaswani (McGraw-Hill, 2005)

External links

• PHP Tutorial - W3 Schools
• PHP.net - Offical PHP Website.