Php1
- 2. PHP PHP Stands for " Hypertext Preprocessor ."
- 3. PHP is an HTML-embedded Web scripting language.
- 4. PHP is an free, open-source server-side scripting language.
- 5. PHP is a server-side scripting language for creating dynamic Web pages.
- 6. This is the most traditional and main target field for PHP.
- 7. To know more about php defintion visit www.phpfordonkeys.com/a719308-php-definition-...
- 8. How PHP Works: When a user navigates in her browser to a page that ends with a .php extension, the request is sent to a web server, which directs the request to the PHP interpreter.
- 9. Basic PHP Syntax : PHP Tags PHP code must be contained in special tags so that the PHP interpreter can identify it. Depending on the PHP configuration, these tags can take several forms: <?php PHP CODE GOES IN HERE ?> It is known as the XML style, because it can be used inside of an XML document.
- 10. HTML OR SCRIPT TAG: <script language="php"> PHP CODE GOES IN HERE </script> ASP-style tags: <% PHP CODE GOES HERE %>
- 11. Comments: PHP has two forms of comments: * Single-line comments begin with a double slash (//). * Multi-line comments begin with "/*" and end with "*/". Syntax // This is a single-line comment /* This is a multi-line comment.*/
- 12. Variables: PHP variables begin with a dollar sign ($) as shown below. Syntax: $var_name = "Value"; Each php statement must ends with semicolon.
- 13. PHP Functions: There are literally hundreds of built-in PHP functions. A function might take zero arguments or several arguments (e.g, mail(), which takes three required and two optional arguments). The syntax for calling a function is straightforward: function_name(arguments);
- 14. Sample code:PhpBasics/Demos/PhpInfo.php <html> <head> <title>PHPINFO</title> </head> <body> <?php //Output information on the PHP environment phpinfo(); ?> </body> </html>
- 15. The php.ini file The php.ini is the main PHP configuration file . php.ini file controls many aspect of php's behavior.
- 16. To read PHP, it must be named 'php.ini' .
- 17. It allows the user to define some of the settings for the PHP interprter .
- 18. SYNTAX: The syntax of the file is extremely simple.
- 19. Whitespace and Lines beginning with a semicolon are silently ignored. Directives : directive = value Directive names are* case sensitive * - foo=bar is different from FOO=bar.
- 20. Expressions in the INI file are limited to bitwise operators : |- bitwise OR
- 21. & -bitwise AND
- 22. ~ -bitwise NOT
- 23. !-boolean NOT Boolean flags can be turned on using the values 1, On, True or Yes. They can be turned off using the values 0, Off, False or No.
- 24. OBJECT ORIENTED FEATURES: PHP scripting language provides object oriented features through the class keyword. We can use the following coding conventions to distinguish between private, public and protected variables: All private variables and functions always start with underscore "_" followed by lowercase letters like var $_myvar;
- 25. All Protected variables and functions always start with "_T" followed by lowercase letters like var $_Tmyvar
- 26. All Public variables and functions do not start with underscore "_" like var $myvar;
- 27. All variables and functions always start with lowercase letter (no uppercase) like var $_myvar; and NOT like var $_Myvar;
- 28. File Uploads: To allow HTTP file uploads.
- 30. Temporary directory for HTTP uploaded files (will use system default if not specified).
- 32. upload_tmp_dir =Maximum allowed size for uploaded files.
- 34. visit www.reallylinux.com/docs/php.ini for more syntax
- 35. Limitations of PHP : PHP is NOT 100 % pure Object Oriented scripting language. But in near future PHP may support 100% object oriented scripting.
- 36. PHP will NOT give the performance of "C" or "C++" language. Because it is scripting language and is interpreted it will be a bit slower than the optimized "C++" programs.
- 37. Advantages: We can very rapidly develop web applications in PHP as compile and link is eliminated in PHP scripting language.
- 38. PHP applications are very stable and do not depend on the browser technologies unlike Javascript applications which depend on browsers.
- 39. PHP will give you the freedom to select any server platform.
- 40. PHP has excellent database conectivity to all SQL database servers.
- 41. PHP has C++, PERL, Javascript like syntax features and has programs like 'ptags/ctags' to navigate the source code
- 42. PHP runs on all UNIX'es, linux, Windows 95/NT/2000 and is more powerful than ASP, JSP and others.
- 43. PHP has a very large user base and developer base.