PHPCourse2020/05_arrays.php at master · thecodeholic/PHPCourse2020 · GitHub

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<?php

// Create array
$fruits = ["Banana", "Apple", "Orange"];

// Print the whole array
echo '<pre>';
var_dump($fruits); // print_r
echo '</pre>';

// Get element by index
echo $fruits[1].'<br>';

// Set element by index
$fruits[0] = "Peach";

// Check if array has element at index 2
echo '<pre>';
var_dump(isset($fruits[2]));  // Change age into 5
echo '</pre>';

// Append element
$fruits[] = 'Peach';
echo $fruits[3].'<br>';

// Print the length of the array
echo count($fruits).'<br>';

// Add element at the end of the array
array_push($fruits, 'Foo');
// Remove element from the end of the array
array_pop($fruits);

echo '<pre>';
var_dump($fruits);
echo '</pre>';

// Add element at the beginning of the array
array_unshift($fruits, 'Apple');
// Remove element from the beginning of the array
array_shift($fruits);

// Split the string into an array
$string = "Banana,Apple,Peach";
echo '<pre>';
var_dump(explode(",", $string));
echo '</pre>';

print_r($fruits);

// Combine array elements into string
echo implode(",", $fruits).'<br>';

// Check if element exist in the array
echo '<pre>';
var_dump(in_array('Apple', $fruits));
echo '</pre>';

// Search element index in the array
echo '<pre>';
var_dump(array_search("Peach", $fruits));
echo '</pre>';

// Merge two arrays
$vegetables = ['Potato', 'Cucumber'];
echo '<pre>';
var_dump(array_merge($fruits, $vegetables));
var_dump([...$fruits, ...$vegetables]); // Since PHP 7.4
echo '</pre>';

// Sorting of array (Reverse order also)
sort($fruits); //sort, rsort, usort
echo '<pre>';
var_dump($fruits);
echo '</pre>';

// Filter, map, reduce of array
$numbers = [1, 2, 3, 4, 5, 6, 7, 8];
$evens = array_filter($numbers, function($n){ // fn($n) => $n % 2 === 0
    return $n % 2 === 0;
});
echo '<pre>';
var_dump($evens);
echo '</pre>';

$squares = array_map(fn($n) => $n + 1, $numbers);
echo '<pre>';
var_dump($squares);
echo '</pre>';

$sum = array_reduce($numbers, fn($carry, $item) => $carry + $item);
echo $sum.'<br>';

// https://www.php.net/manual/en/ref.array.php

// ============================================
// Associative arrays
// ============================================

// Create an associative array
$person = [
    'name' => 'Brad',
    'surname' => 'Traversy',
    'age' => 30,
    'hobbies' => ['Tennis', 'Video Games'],
];
// Get element by key
echo $person['name'].'<br>';

// Set element by key
$person['channel'] = 'TraversyMedia';

// Check if array has specific key
echo '<pre>';
var_dump(isset($person['age']));  // Change age into "location"
echo '</pre>';

// Print the keys of the array
echo '<pre>';
var_dump(array_keys($person));
echo '</pre>';

// Print the values of the array
echo '<pre>';
var_dump(array_values($person));
echo '</pre>';

// Sorting associative arrays by values, by keys
ksort($person); // ksort, krsort, asort, arsort
echo '<pre>';
var_dump($person);
echo '</pre>';


// Two dimensional arrays
$todoItems = [
    ['title' => 'Todo1', 'completed' => true],
    ['title' => 'Todo 2', 'completed' => false],
];

echo '<pre>';
var_dump($todoItems);
echo '</pre>';