PHP For Absolute Beginners

Talk given at the Winnipeg WordPress Meetup on March 6, 2013.

Transcript

1. PHP For Absolute
   Beginners
   Matt Wiebe
   @mattwiebe
   wp.mattwie.be
   Design Engineer
   Automattic / WordPress.com
   

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2. PHP
   

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3. PHP
   

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5. PHP
   For people who may or may not know what that is.
   

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6. What is PHP?
   

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7. What is PHP?
   ★ The thing that makes WordPress work
   

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8. What is PHP?
   ★ The thing that makes WordPress work
   ★ The thing you should know a little bit
   about if you want to tweak a theme or
   plugin.
   

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9. What is PHP?
   ★ The thing that makes WordPress work
   ★ The thing you should know a little bit
   about if you want to tweak a theme or
   plugin.
   ★ PHP: Hypertext Preprocessor
   

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11. What is PHP?
    ★ The thing that makes WordPress work
    ★ The thing you should know a little bit
    about if you want to tweak a theme or
    plugin.
    ★ PHP: Hypertext Preprocessor
    ★ The easiest way to get started with
    programming.
    

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12. What is PHP?
    ★ The thing that makes WordPress work
    ★ The thing you should know a little bit
    about if you want to tweak a theme or
    plugin.
    ★ PHP: Hypertext Preprocessor
    ★ The easiest way to get started with
    programming. (except maybe JavaScript)
    

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13. What is PHP?
    
    
    
    
    
    

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14. What is PHP?
    
    
    
    
    
    
    

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15. What is PHP?
    
    
    
    
    
    
    

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16. What is PHP?
    
    
    
    
    
    
    

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18. Why should I learn PHP?
    

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19. Why should I learn PHP?
    ★ It’s what makes WordPress sing and dance
    

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20. Why should I learn PHP?
    ★ It’s what makes WordPress sing and dance
    ★ It’s easy
    

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21. Why should I learn PHP?
    ★ It’s what makes WordPress sing and dance
    ★ It’s easy
    ★ It’s fun
    

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22. Why should I learn PHP?
    ★ It’s what makes WordPress sing and dance
    ★ It’s easy
    ★ It’s fun
    ★ It might turn a hobby into a career
    

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23. THE BASICS
    

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24. Variables
    

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25. Variables
    $my_string = 'bar';
    

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26. Variables
    $my_string = 'bar';
    

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27. Variables
    $my_string = 'bar';
    // This is a comment. It is ignored.
    

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28. Variables
    $my_string = 'bar';
    // This is a comment. It is ignored.
    $my_number = 3;
    

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29. Variables
    $my_string = 'bar';
    // This is a comment. It is ignored.
    $my_number = 3;
    $my_array = array('one', 'two', 'ten');
    

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30. Variables
    $my_string = 'bar';
    // This is a comment. It is ignored.
    $my_number = 3;
    $my_array = array('one', 'two', 'ten');
    $my_boolean = true;
    

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31. Variables
    $my_string = 'bar';
    // This is a comment. It is ignored.
    $my_number = 3;
    $my_array = array('one', 'two', 'ten');
    $my_boolean = true;
    /* Now you've seen 4 types of data */
    

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32. Operations
    

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33. Operations
    $first_name = 'Matt';
    $last_name = 'Wiebe';
    

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34. Operations
    $first_name = 'Matt';
    $last_name = 'Wiebe';
    // Concatenation
    $full_name = $first_name . ' ' . $last_name;
    

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35. Operations
    $my_age = 33;
    $my_nephews_age = 3;
    

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36. Operations
    $my_age = 33;
    $my_nephews_age = 3;
    // Simple numeric operations: +-*/
    $age_difference = $my_age - $my_nephews_age;
    

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37. Comparisons
    

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38. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    

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39. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    $my_name == $dans_name
    

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40. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    $my_name == $dans_name;
    

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41. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    $my_name == $dans_name;
    // false;
    

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42. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    $my_name == $dans_name;
    // false;
    $my_name == $my_bosses_name;
    

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43. Comparisons
    $my_name = 'Matt';
    $dans_name = 'Dan';
    $my_bosses_name = 'Matt';
    $my_name == $dans_name;
    // false;
    $my_name == $my_bosses_name;
    // true;
    

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44. Comparisons
    $a == $b // Equal
    $a != $b // Not equal
    $a >= $b // $a greater than or equal to $b
    $a <= $b // $a less than or equal to $b
    $a > $b // $a greater than $b
    $a < $b // $a less than $b
    

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45. Comparisons
    $a == $b // Equal
    $a != $b // Not equal
    $a >= $b // $a greater than or equal to $b
    $a <= $b // $a less than or equal to $b
    $a > $b // $a greater than $b
    $a < $b // $a less than $b
    /* There are a lot more but
    that’s all we’ll cover now. */
    

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46. Using Comparisons
    if ( $a == $b ) {
    }
    

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47. Using Comparisons
    if ( $a == $b ) {
    }
    

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48. Using Comparisons
    if ( $a == $b ) {
    // do something
    }
    

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49. Using Comparisons
    if ( $a == $b ) {
    // do something
    }
    else {
    }
    

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50. Using Comparisons
    if ( $a == $b ) {
    // do something
    }
    else {
    // do something else
    }
    

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51. Functions
    

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52. Functions
    

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54. Functions
    $name = 'Matt Wiebe';
    

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55. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    

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56. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    

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57. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    

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58. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    

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59. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    

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60. Functions
    $name = 'Matt Wiebe';
    $fun = str_replace( 'Matt', 'Jerk', $name );
    echo $fun;
    // 'Jerk Wiebe'
    

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61. WordPress Functions
    

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62. WordPress Functions
    In WordPress, template tags are
    PHP functions.
    

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64. WordPress Functions
    Home
    

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65. WordPress Functions
    Home
    

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66. WordPress Functions
    Home
    
    
    
    
    
    
    
    
    

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67. WordPress Functions
    Home
    
    
    
    
    
    
    
    
    

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68. WordPress Functions
    Home
    
    
    
    
    
    
    
    
    

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69. WordPress Functions
    Home
    
    
    
    
    
    
    
    
    

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70. WordPress Functions
    Home
    
    
    
    
    
    
    
    
    

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71. WordPress Functions
    ★ Read the Codex:
    

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72. WordPress Functions
    ★ Read the Codex:
    ★ codex.wordpress.org
    

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73. WordPress Functions
    ★ Read the Codex:
    ★ codex.wordpress.org
    ★ Learn the template hierarchy
    

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74. WordPress Functions
    ★ Read the Codex:
    ★ codex.wordpress.org
    ★ Learn the template hierarchy
    ★ codex.wordpress.org/Template_Hierarchy
    

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75. WordPress Functions
    ★ Read the Codex:
    ★ codex.wordpress.org
    ★ Learn the template hierarchy
    ★ codex.wordpress.org/Template_Hierarchy
    ★ Make a child theme to hack on
    

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76. WordPress Functions
    ★ Read the Codex:
    ★ codex.wordpress.org
    ★ Learn the template hierarchy
    ★ codex.wordpress.org/Template_Hierarchy
    ★ Make a child theme to hack on
    ★ codex.wordpress.org/Child_Themes
    

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77. WordPress Functions
    ★ Learn the template tags (functions):
    

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78. WordPress Functions
    ★ Learn the template tags (functions):
    ★ codex.wordpress.org/Template_Tags
    

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80. ?>
    Matt Wiebe
    @mattwiebe
    wp.mattwie.be
    Design Engineer
    Automattic / WordPress.com
    

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