1. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC Introduction to & Overview of PHP Instructor: Joseph DiVerdi, Ph.D., MBA

2. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP In Brief PHP Is A –Server-Side –HTML-Embedded –Cross-Platform –Programming Language Provides a Means for Developers to Put Instructions in HTML Files to Create Dynamic Content

3. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC Explanations Server-Side –PHP Code is Executed on the Server HTML-Embedded –PHP Code is Inserted Directly in HTML Cross-Platform –PHP Runs on Several Different (Server) OSes Scripting Language –Difference Between Scripting & Programming Languages is Increasingly Small More Semantic than Significant –Script is Not Compiled

4. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP in Less Brief PHP Provides a Means for Developers –To Put Instructions in HTML Files –The Instructions are Read & Parsed by Server They Never Make It to the Browser –The Server Replaces PHP Code with Content HTML etc. –Forerunner Technology is Server Side Includes (SSI)

5. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC Other Developments Need for HTML-Embedded Server-Side Scripting Technology was Apparent to Others Microsoft went after this need with ASP –Active Server Pages ASP Has Become Quite Popular –In Microsoft Shops Many Developers Sought More Stable & Less Proprietary Solution –Enter PHP, an Open-Source Server-Parsed HTML-Embedded Programming Language

6. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Benefits PHP's Primary Strength –Rapid Development of Web Pages With Modest Amount of Dynamic Content –Developers Without Heavy Programming Experience Enjoy PHP's Shallow Learning Curve –Complete Tasks Of Modest Complexity Pulling Records From a Database & Inserting Them Into an HTML Table

7. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Benefits PHP Language Architecture –Simple but Powerful –Includes an Extremely Wide Variety of Functions Suited for Many Tasks –Traditional Data Processing –Web-Oriented Functions

8. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example Welcome!

9. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Weaknesses PHP Remains an Immature Language –Without the Architectural Strengths or Extensibility of More Established Languages Embedded Scripting –Program Code is Mixed With HTML Some Developers Are Empowered By This Others Find It Disorganized & Error-Prone –Prefer Separate Development Environments For Each Web Component

10. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Weaknesses Advanced Developers –With Experience in Perl, CGI, & mod_perl May Find Less Reason to Spend Time with PHP And This May be Entirely Justified –Because They Can Already Do What PHP Can

11. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Strengths Developers Have Literally Flocked to PHP –Modest Learning Curve –Free & Open Development –Native Database Connectivity –Stability –Availability for a Variety of Server Platforms

12. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC In Summary It is Important to Understand That PHP is not a Unique Solution to Web Development –We're Fortunate to Enjoy a Potpourri of Possible Web Development Tools Many Tasks can be Performed with a Wide Variety of Technologies –Developers Must Weigh Many Factors in Choosing a Development Path Previous & Current Experience Platform Requirements & Support Time-to-Market Requirements

13. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Documentation PHP Is Still in an Early Stage of Development Language Continues to Evolve Significantly Printed Texts Tend to Lag Behind Most Current Information Available On-Line PHP On-Line Manual http://www.php.net/manual/en/

14. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example PHP Test Page Create File Named "php_info.php"

15. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example PHP Test Page Here is some text. "); ?> Create File Named "test.php"

16. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example <?PHP print(" \n"); print("Here is some text.\n"); print(" \n"); ?> Modify "test.php"

17. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example PHP Date Page <?PHP print(" \n"); print("The current date is: "); print(date("l F j, Y")); print(" \n"); ?> Create File Named "date.php"

18. PHP Introduction & Overview Fort Collins, CO Copyright © XTR Systems, LLC PHP Example PHP Time & Date Page <?PHP print(" \n"); print("The current time and date are: "); print(date("H:i:s \M\T, l F j, Y")); print(" \n"); ?> Modify "date.php"