Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Web Scripting using PHP
Web Scripting using PHP   Server side scripting
So what is a Server Side Scripting Language?• Programming language code embedded into a web  page                     PERL...
So what is a Server Side Scripting Language?• Programming language code embedded into a web  page                     PERL...
Different ways of scripting the Web• Programming language code embedded into a web  page           No scripting (plain mar...
No Scripting example - how it works...User on a machine somewhere                                     Ser ver machine
Being more specific...
Web Browser soft ware
Web ser versoft ware
User types in a URL for a page with noprogramming code inside
User types in a URL for a page with noprogramming code insideUniform Resource Locator
Request is sent toser ver using HTTP
Request is sent to                              ser ver using HTTPHypertext Transfer Protocol
Ser ver soft warefinds the page
Page is sent back,using HTTP
Browser renders /displays the page
Server Side scripting
User types in a URL for a page withPHP code inside
Request is sent toser ver using HTTP
Ser ver soft warefinds the page
Ser ver side codeis executed
Page is sent back,using HTTP
Browser renders /displays the page
Server side scripting languages • Executes in the ser ver • Before the page is sent from server to browser • Ser ver side ...
Browser            Web ser ver          Database ser ver
How many items in stock?
HTTP request
Web ser verexecutes code
Web ser ver    executes codeQueriesdatabaseser ver
Resultsentback
HTMLgenerated
HTTP response
Answer displayed
So why PHP?               PERL               PHP              PYTHON               ASP
PHP usage ...                • Source: PHP programming 2nd Ed.
PHP compared to others ...                         • Source: www.securityspace.com
Books - core syntaxProgramming PHP, Second Edition    PHP in a NutshellBy Kevin Tatroe, Rasmus Lerdorf,   By Paul HudsonPe...
Books - learning / tutorial basedLearning PHP 5             Learning PHP and MySQLBy David Sklar             By Michele Da...
Other texts..  • There are other publishers / texts (trade books)  • Look for books that cover PHP 5  • Open source, serve...
PHP development                                        PHP 5                           PHP 4          PHP 3  PHP 1        ...
Language basics
Language basics    •   Embedding PHP in Web pages    •   Whitespace and Line breaks    •   Statements and semicolons    • ...
Language basics    •   Embedding PHP in Web pages    •   Whitespace and Line breaks    •   Statements and semicolons    • ...
Embedding PHP in web pages                     Use <?php and ?> to   <?php             surround the php code   statement; ...
Embedding PHP in web pages   <?php   statement;statement;    statement;               statement;      statement;statement;...
The legendary Hello World program  <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01     Transitional//EN"   "http://www.w3.org/...
The legendary Hello World program  <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01     Transitional//EN"   "http://www.w3.org/...
The legendary Hello World program  <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01     Transitional//EN"   "http://www.w3.org/...
PHP can be put ‘ nywhere’..               a                      All the php blocks are processed  <html>  <?php ... ?>   ...
PHP can be put ‘ nywhere’.. but works in sequence               a  <html>  <?php ... ?>               Starting at the top ...
Statements and semicolons                     Use ; to separate   <?php             statements   statement;   statement;  ...
All of these would work the same way...<?php statement; statement;statement ?><?phpstatement; statement;statement;?><?phps...
CommentsMany different ways to add commentsComment            Source                 Action    //                C++      ...
Comments  <?php  php statement; // A comment here  php statement; # Another comment here  /* A series of lines  with comme...
Comments   <?php   php statement; // A comment here   php statement; # Another comment here   /* A series of lines   with ...
Language basics    •   Embedding PHP in Web pages    •   Whitespace and Line breaks    •   Statements and semicolons    • ...
Language basics    •   Embedding PHP in Web pages   ✔    •   Whitespace and Line breaks   ✔    •   Statements and semicolo...
LiteralsA data value that appears directly in the program 2001                         An integer 0xFE                   H...
IdentifiersIdentifiers (or names) in PHP must - Begin with an ASCII letter (uppercase or lowercase)       or begin with the ...
VariablesVariables in PHP are identifiers prefixed by $    $bill    $value_count    $anothervalue3                Valid    $...
Case sensitivity - names we define are case sensitive  $value                         Three different names  $VALUE  $vaLUE
VariablesWe use variables for items of data that will changeas the program runsChoose a sensible name and have as many as ...
VariablesWhen we declare a variable, a space is reservedand labelled for that item (in memory)     $bill                  ...
VariablesTo give it a value, use the equals sign      $bill                                    $bill
VariablesTo give it a value, use the equals sign      $bill = 42                                    $bill
VariablesTo give it a value, use the equals sign      $bill = 42                     42                                   ...
VariablesTo give it a value, use the equals sign      $bill                                    $bill
VariablesTo give it a value, use the equals sign      $bill = 57.98                                    $bill
VariablesTo give it a value, use the equals sign      $bill = 57.98                57.98                                  ...
VariablesTo give it a value, use the equals sign      $bill                                          $bill
VariablesTo give it a value, use the equals sign      $bill = “No payment”                                          $bill
VariablesTo give it a value, use the equals sign      $bill = “No payment”         “No payment”                           ...
VariablesIf a value is changed, the old value is over written      $bill                                   $bill
VariablesIf a value is changed, the old value is over written      $bill = 42;                                   $bill
VariablesIf a value is changed, the old value is over written      $bill = 42;                   42                       ...
VariablesIf a value is changed, the old value is over written      $bill = 42;                   42      $bill = 58;      ...
VariablesIf a value is changed, the old value is over written      $bill = 42;                   58      $bill = 58;      ...
VariablesSometimes we use the old value to recalculate thenew value     $bill                                 $bill
VariablesSometimes we use the old value to recalculate thenew value     $bill = 42;                                 $bill
VariablesSometimes we use the old value to recalculate thenew value     $bill = 42;                 42                    ...
VariablesSometimes we use the old value to recalculate thenew value     $bill = 42;                 42     $bill = $bill*2...
VariablesSometimes we use the old value to recalculate thenew value     $bill = 42;                 84     $bill = $bill*2...
VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42;      ...
VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42;      ...
VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42;      ...
VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42;      ...
Keywords                   _CLASS_ _       Declare        extends           print( )                   _ _FILE_ _      Def...
Data typesPHP provides 8 types scalar (single-value)           compound       integers                    arrays     floati...
IntegersWhole numbers - range depends on the C compilerthat PHP was made in (compiled in)Typically          +2,147,483,647...
Floating-Point NumbersReal numbers - again range is implementation specificTypically         1.7E-308 to 1.7E+308 with 15  ...
StringsDelimited by either single or double quotes           ‘here is a string’           “here is another string”
Strings - single quotesYou can use single quotes to enclose double quotes    $outputstring=‘He then said “Goodbye” and lef...
Strings - double quotesYou can use double quotes to enclose single quotes    $outputstring=”He then said ‘Goodbye’ and lef...
OperatorsStandard arithmetic operators: +, -, *, /, % ..Concatenation operator:      .     $outputstring=”He then said “.$...
Operators$aBool=true;$anInt=156;$aFloat=12.56;$anotherFloat=12.2E6;$massiveFloat=12.2E-78;print "The bool printed looks li...
Operators$aBool=true;$anInt=156;$aFloat=12.56;$anotherFloat=12.2E6;$massiveFloat=12.2E-78;print "The bool printed looks li...
Upcoming SlideShare
Loading in …5
×
Upcoming SlideShare
06 laboratory exercise 1
Next

0

Share

php app development 1

Slides used from an introduction to PHP

Related Books

Free with a 30 day trial from Scribd

See all
  • Be the first to like this

php app development 1

  1. 1. Web Scripting using PHP
  2. 2. Web Scripting using PHP Server side scripting
  3. 3. So what is a Server Side Scripting Language?• Programming language code embedded into a web page PERL PHP PYTHON ASP
  4. 4. So what is a Server Side Scripting Language?• Programming language code embedded into a web page PERL PHP PYTHON ASP
  5. 5. Different ways of scripting the Web• Programming language code embedded into a web page No scripting (plain markup) Client Side scripting Ser ver Side scripting Combination of the above (AJAX)
  6. 6. No Scripting example - how it works...User on a machine somewhere Ser ver machine
  7. 7. Being more specific...
  8. 8. Web Browser soft ware
  9. 9. Web ser versoft ware
  10. 10. User types in a URL for a page with noprogramming code inside
  11. 11. User types in a URL for a page with noprogramming code insideUniform Resource Locator
  12. 12. Request is sent toser ver using HTTP
  13. 13. Request is sent to ser ver using HTTPHypertext Transfer Protocol
  14. 14. Ser ver soft warefinds the page
  15. 15. Page is sent back,using HTTP
  16. 16. Browser renders /displays the page
  17. 17. Server Side scripting
  18. 18. User types in a URL for a page withPHP code inside
  19. 19. Request is sent toser ver using HTTP
  20. 20. Ser ver soft warefinds the page
  21. 21. Ser ver side codeis executed
  22. 22. Page is sent back,using HTTP
  23. 23. Browser renders /displays the page
  24. 24. Server side scripting languages • Executes in the ser ver • Before the page is sent from server to browser • Ser ver side code is not visible in the client • Ser ver side code can access resources on the server side
  25. 25. Browser Web ser ver Database ser ver
  26. 26. How many items in stock?
  27. 27. HTTP request
  28. 28. Web ser verexecutes code
  29. 29. Web ser ver executes codeQueriesdatabaseser ver
  30. 30. Resultsentback
  31. 31. HTMLgenerated
  32. 32. HTTP response
  33. 33. Answer displayed
  34. 34. So why PHP? PERL PHP PYTHON ASP
  35. 35. PHP usage ... • Source: PHP programming 2nd Ed.
  36. 36. PHP compared to others ... • Source: www.securityspace.com
  37. 37. Books - core syntaxProgramming PHP, Second Edition PHP in a NutshellBy Kevin Tatroe, Rasmus Lerdorf, By Paul HudsonPeter MacIntyre First Edition October 2005Second Edition April 2006** Recommended
  38. 38. Books - learning / tutorial basedLearning PHP 5 Learning PHP and MySQLBy David Sklar By Michele Davis, Jon PhillipsFirst Edition June 2004 First Edition June 2006
  39. 39. Other texts.. • There are other publishers / texts (trade books) • Look for books that cover PHP 5 • Open source, server side languages can rapidly develop • Features added or deprecated rapidly
  40. 40. PHP development PHP 5 PHP 4 PHP 3 PHP 1 • 5 versions in 10 years
  41. 41. Language basics
  42. 42. Language basics • Embedding PHP in Web pages • Whitespace and Line breaks • Statements and semicolons • Comments • Literals / names • Identifiers • Keywords • Data types
  43. 43. Language basics • Embedding PHP in Web pages • Whitespace and Line breaks • Statements and semicolons • Comments • Literals / names • Identifiers • Keywords • Data types Much of this material is explained in PHP programming 2nd Ed. Chap 1 & 2
  44. 44. Embedding PHP in web pages Use <?php and ?> to <?php surround the php code statement; statement; statement ?>
  45. 45. Embedding PHP in web pages <?php statement;statement; statement; statement; statement;statement; ?> In general whitespace doesn’t matter Use indenting and separate lines to create readable code
  46. 46. The legendary Hello World program <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <title>This is the first PHP program</title> </head> <body> <p> <?php print "Hello World!"; ?> </p> </body> </html>
  47. 47. The legendary Hello World program <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <title>This is the first PHP program</title> </head> <body> <p> <?php print "Hello World!"; ?> </p> </body> </html>
  48. 48. The legendary Hello World program <!DOCTYPE HTML PUBLIC "-//W3C/DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <title>This is the first PHP program</title> </head> <body> <p> print sends a sequence of <?php print "Hello World!"; characters to the output ?> </p> The sequence here is </body> indicated by start and </html> end quotes
  49. 49. PHP can be put ‘ nywhere’.. a All the php blocks are processed <html> <?php ... ?> before the page is sent <head> <?php ... ?> <title>... <?php ... ?> ...</title> </head> <body> <p> <?php ... ?> </p> </body> </html>
  50. 50. PHP can be put ‘ nywhere’.. but works in sequence a <html> <?php ... ?> Starting at the top <head> <?php ... ?> <title>... <?php ... ?> ...</title> </head> <body> <p> <?php ... ?> Working down to the bottom </p> </body> </html>
  51. 51. Statements and semicolons Use ; to separate <?php statements statement; statement; statement; ?>
  52. 52. All of these would work the same way...<?php statement; statement;statement ?><?phpstatement; statement;statement;?><?phpstatement;statement; This is the best way ofstatement; laying the code out?>
  53. 53. CommentsMany different ways to add commentsComment Source Action // C++ Comments to EOL # Unix shell scripting Comments to EOL /* and */ C Comments out a block
  54. 54. Comments <?php php statement; // A comment here php statement; # Another comment here /* A series of lines with comments ignored by the PHP processor */ php statement; ?>
  55. 55. Comments <?php php statement; // A comment here php statement; # Another comment here /* A series of lines with comments ignored by the PHP processor */ php statement; ?>Everything in red is ignored by the PHP interpreter
  56. 56. Language basics • Embedding PHP in Web pages • Whitespace and Line breaks • Statements and semicolons • Comments • Literals / names • Identifiers • Keywords • Data types
  57. 57. Language basics • Embedding PHP in Web pages ✔ • Whitespace and Line breaks ✔ • Statements and semicolons ✔ • Comments ✔ • Literals / names • Identifiers • Keywords • Data types
  58. 58. LiteralsA data value that appears directly in the program 2001 An integer 0xFE Hexadecimal number 1.4142 Float “Hello World” String ‘Hi’ String true Bool null built in ‘no value’ symbol
  59. 59. IdentifiersIdentifiers (or names) in PHP must - Begin with an ASCII letter (uppercase or lowercase) or begin with the underscore character _ or any character bet ween ASCII 0x7F to 0xFF followed by any of these characters and the digits 0-9
  60. 60. VariablesVariables in PHP are identifiers prefixed by $ $bill $value_count $anothervalue3 Valid $THIS_IS_NOT_A_GOOD_IDEA $_underscore $not valid Invalid $[ $3wa
  61. 61. Case sensitivity - names we define are case sensitive $value Three different names $VALUE $vaLUE
  62. 62. VariablesWe use variables for items of data that will changeas the program runsChoose a sensible name and have as many as youlike $total_income $bill $salary $month $total $percentage_increase
  63. 63. VariablesWhen we declare a variable, a space is reservedand labelled for that item (in memory) $bill $bill
  64. 64. VariablesTo give it a value, use the equals sign $bill $bill
  65. 65. VariablesTo give it a value, use the equals sign $bill = 42 $bill
  66. 66. VariablesTo give it a value, use the equals sign $bill = 42 42 $bill
  67. 67. VariablesTo give it a value, use the equals sign $bill $bill
  68. 68. VariablesTo give it a value, use the equals sign $bill = 57.98 $bill
  69. 69. VariablesTo give it a value, use the equals sign $bill = 57.98 57.98 $bill
  70. 70. VariablesTo give it a value, use the equals sign $bill $bill
  71. 71. VariablesTo give it a value, use the equals sign $bill = “No payment” $bill
  72. 72. VariablesTo give it a value, use the equals sign $bill = “No payment” “No payment” $bill
  73. 73. VariablesIf a value is changed, the old value is over written $bill $bill
  74. 74. VariablesIf a value is changed, the old value is over written $bill = 42; $bill
  75. 75. VariablesIf a value is changed, the old value is over written $bill = 42; 42 $bill
  76. 76. VariablesIf a value is changed, the old value is over written $bill = 42; 42 $bill = 58; $bill
  77. 77. VariablesIf a value is changed, the old value is over written $bill = 42; 58 $bill = 58; $bill
  78. 78. VariablesSometimes we use the old value to recalculate thenew value $bill $bill
  79. 79. VariablesSometimes we use the old value to recalculate thenew value $bill = 42; $bill
  80. 80. VariablesSometimes we use the old value to recalculate thenew value $bill = 42; 42 $bill
  81. 81. VariablesSometimes we use the old value to recalculate thenew value $bill = 42; 42 $bill = $bill*2 ; $bill
  82. 82. VariablesSometimes we use the old value to recalculate thenew value $bill = 42; 84 $bill = $bill*2 ; $bill
  83. 83. VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42; Stores an integer $bill=42; $bill=”Now its a string”; print $bull;
  84. 84. VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42; Stores an integer $bill=42; Over writes with a string $bill=”Now its a string”; print $bull;
  85. 85. VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42; Stores an integer $bill=42; Over writes with a string $bill=”Now its a string”; Whoops - made a mistake print $bull; but it still works
  86. 86. VariablesSome languages are very strict about what kinds ofdata are stored in variables - PHP doesn’t care $bill=42; Stores an integer $bill=42; Over writes with a string $bill=”Now its a string”; Whoops - made a mistake print $bull; but it still works
  87. 87. Keywords _CLASS_ _ Declare extends print( ) _ _FILE_ _ Default final privateReserved by _ _FUNCTION_ _ die( ) for protectedthe language _ _LINE_ _ Do foreach publicfor core _ _METHOD_ _ echo( ) function require( ) Else globalfunctionality Abstract And elseif if require_once( ) array( ) empty( ) implements return( ) As enddeclare include( ) static Break endfor include_once( ) switchAlso - can’t Case catch endforeach interface tHRow endif isset( )use a built in cfunction endswitch list( ) TRy unset( )function Class endwhile new use clonename as a Const eval( ) old_function var exception Orvariable Continue exit( ) php_user_filter while xor
  88. 88. Data typesPHP provides 8 types scalar (single-value) compound integers arrays floating-point objects string booleans Two are special - resource and NULL
  89. 89. IntegersWhole numbers - range depends on the C compilerthat PHP was made in (compiled in)Typically +2,147,483,647 to -2,147,483,647 Octal 0755 Hexadecimal 0xFFLarger integers get converted to floats automatically
  90. 90. Floating-Point NumbersReal numbers - again range is implementation specificTypically 1.7E-308 to 1.7E+308 with 15 digits of accuracyExamples 3.14, 0.017, -7.1, 0.314E1, 17.0E-3
  91. 91. StringsDelimited by either single or double quotes ‘here is a string’ “here is another string”
  92. 92. Strings - single quotesYou can use single quotes to enclose double quotes $outputstring=‘He then said “Goodbye” and left’;Useful for easily printing HTML attributes $outputstring=‘<a href=”http:/www.bbc.co.uk”>BBC</a>’;
  93. 93. Strings - double quotesYou can use double quotes to enclose single quotes $outputstring=”He then said ‘Goodbye’ and left”;
  94. 94. OperatorsStandard arithmetic operators: +, -, *, /, % ..Concatenation operator: . $outputstring=”He then said “.$quote;Any non-string value is converted to a string beforethe concatenation.
  95. 95. Operators$aBool=true;$anInt=156;$aFloat=12.56;$anotherFloat=12.2E6;$massiveFloat=12.2E-78;print "The bool printed looks like this: ".$aBool."<br />";print "The int printed looks like this: ".$anInt."<br />";print "The (smaller) float printed looks like this: ".$aFloat."<br />";print "The larger float printed looks like this: ".$anotherFloat."<br />";print "The even larger float printed looks like this: ".$massiveFloat."<br />";
  96. 96. Operators$aBool=true;$anInt=156;$aFloat=12.56;$anotherFloat=12.2E6;$massiveFloat=12.2E-78;print "The bool printed looks like this: ".$aBool."<br />";print "The int printed looks like this: ".$anInt."<br />";print "The (smaller) float printed looks like this: ".$aFloat."<br />";print "The larger float printed looks like this: ".$anotherFloat."<br />";print "The even larger float printed looks like this: ".$massiveFloat."<br />";

Slides used from an introduction to PHP

Views

Total views

2,802

On Slideshare

0

From embeds

0

Number of embeds

926

Actions

Downloads

1

Shares

0

Comments

0

Likes

0

×