Watkins Web 3: Blog

Cheat Sheet: Review of PHP Fundamentals

Variables

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$string = "Tennessee";
$age = 24;
$double_age = 2 * $age;
$age_plus_ten = $age + 10;

Arrays

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// numeric array (AKA indexed array)
    $items[0] = "orange";
    $items[1] = "apple";
    $items[2] = "pear";
    echo $items[1];         // outputs apple
    // associative array
    $items[username] = "Joe";
    $items[school] = "Watkins";

Conditions (Control Structures)

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if ( $age > 20 ) {
        echo "you are older than 20";
        echo " and that is great.";
        }
    else {
            echo "you are younger than 20";
    }

Functions

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// built-in to PHP
    $the_year_now = date('Y'); // stores 2012 in my variable
    // build your own
    function year_plus_one() {
        $output = 1 + date('Y');
        return $output;
        }
    $the_year_plus_one = year_plus_one();
    $the_year_plus_two = $the_year_plus_one + 1;
    echo $the_year_plus_two; // outputs 2014

Loops

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// FOR loop
        for ($i = 1; $i <=10; $i++) {   
            echo ("the counter is at $i");
            }
    // FOREACH loop (only for arrays)
        $items[username] = "Joe";
        $items[school] = "Watkins";
    foreach ($items as $key => $value) {
            echo ("For this element, the key is $key and the value is $value.");
        }