PHP Code Snippets

$arr = [1, 2, 3, 4, 5, 6, 7, 8, 9];
foreach ($arr as $key => $value) {
    if ($value % 2 == 0) {
        unset($arr['$key']);
    }
}

$numbers = [1, 2, 3, 4, 5];
echo min($numbers); // Outputs 1
echo max($numbers); // Outputs 5

$array = ["Samsung Galaxy Note 10", "Apple iPhone 13 Pro", "Samsung Galaxy Note 10", "Apple iPhone 13 Pro Max", "Apple iPhone 13 Pro"];
$result = array_unique($array);

foreach($users as $key => $user) {
	echo $key.': '.$user;
}
for ($i = 0; $i < count($users); $i++) {
    echo $users[$i];
}

$settings = [
    'send_from_phone' => '',
    'days_before_notify' => '0',
    'time_to_notify' => '09:00',
    'send_from_email' => ''
];

//multi-dimension array
$settings = [
    'receipents' => ['abc@gmail.com', 'xyz@gmail.com', 'another@gmail.com'],
    'working_days' => ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday'],
];

//casting
$array = array('id' => 1, 'name' => 'PHP Example');
$article = (object) $array;

//create blank object and add array values to its fields
$array = ['id' => 2, 'name' => 'Kotlin Example'];
$article2 = new stdClass();
foreach ($array as $key => $value)
{
    $article2->$key = $value;
}

//use json_decode
$array = ['id' => 3, 'name' => 'Flutter Example'];
$article3 = json_decode(json_encode($array), FALSE);

$languages = ["Go", "Dart", "Kotlin", "Swift"];
 
$deletedlanguages  = array_pop($languages);

$japaneseNames = [
        '6' => 'Oda',
        '54' => 'Mitsuru',
        '17' => 'Kenichi',
        '1' => 'Saitama'
    ];
$japaneseNames = array_values($japaneseNames);

$movies = ["The Godfather", "A Few Good Men", "Jurassic Park"];
array_unshift($movies , 'Titanic');

$product1 = new stdClass();
$product1->id = 1;
$product1->name = 'LED Lamp';
$product1->brand = 'Xiao Mi';

$product2 = new stdClass();
$product2->id = 2;
$product2->name = 'Large Meeting Table';

$product = (object) array_merge((array) $product1, (array) $product2);

$invoice = new stdClass();
$invoice->id = 5;
$invoice->number = "INV-2022050005";

$last_day = date("t", strtotime("February"));
echo $last_day; //28

if ( strtotime('2022-05-20') > strtotime(date('Y-m-d', mktime(0, 0, 0, 5, 21, 2022))) )
   // do something
}

if (new DateTime('2022-05-25') < new DateTime()){
	echo 'Expiration date';
}

$datetime = '2019-01-01 12:00:00';
$timestamp = strtotime($datetime);
echo $timestamp; //1546344000

//current timestamp
print strtotime(date('Y-m-d H:i:s'));

print date("d");
print date("m");
print date("Y");
print date("m-d-Y");
print date("Y-m-d H:i:s");

//use timezone name with PHP date
date_default_timezone_set('America/Anchorage');
$datetime = new DateTime('2022-05-22T05:30:00', new DateTimeZone('America/Cordoba'))

$time_start = microtime(true);

for ($i = 0; $i < 100000; $i++) {
    preg_match('/abc/', 'abcdefabc');
}


$time_end = microtime(true);
$time = $time_end - $time_start;
echo "preg_match(): $time <br/><br/><br/>";


$time_start = microtime(true);
for ($i = 0; $i < 100000; $i++) {
    strpos('abcdefabc', 'abc');
}

$time_end = microtime(true);
$time = $time_end - $time_start;
echo "strpos(): $time\n";

$start = microtime(true);
// Enter your code here, enjoy!
$array = array("1" => "Debugging...",
    "emoji" => "😄 😁 😆", 
    "number" => rand(100,999),
    "version" => phpversion()
);

foreach( $array as $key => $value ){
    echo $key."\t=>\t".$value."\n";
}
$end = microtime(true);

echo sprintf("Elapsed:  %f", $end - $start).PHP_EOL;

echo sprintf("Used RAM:  %s bytes", memory_get_usage());

header('Content-type: application/pdf');  
header('Content-Disposition: inline; filename="myPDF.pdf"'); 
header('Content-Transfer-Encoding: binary'); 
header('Accept-Ranges: bytes'); 
@readfile('myPDF.pdf'); 

//redirect user to any page
header('Location: https://example.com/form-handling/');
header('Location: ' . $_SERVER['HTTP_REFERER']);
header("Location: ".$_SERVER['REQUEST_URI']);

//Add the following line to php.ini file
extension=curl

$string = '12.34 Dollars';
$int = intval($string); //12
$float = floatval($string); //12.34

$string = '$12.34 Dollars'; //not starting with a number
$int = intval($string); //0
$float = floatval($string); //0.0

$string = "150.99";
$int = (int) $string; //150
$float = (float) $string; //150.99

$number = "1000.0001";
echo number_format($number, 2, '.', '');
//output: 1000.00
echo number_format($number, 2, '.', ',');
//output: 1,000.00

//round to the nearest 5
$roundedNumber = (ceil($number)%10 === 0) ? ceil($number) : ceil($number/5)*5;
$roundedNumber = (floor($number)%10 === 0) ? floor($number) : floor($number/5)*5;
//round to the nearest 10
$roundedNumber = round($number, -1, PHP_ROUND_HALF_UP);
$roundedNumber = round($number, -1, PHP_ROUND_HALF_DOWN);
$roundedNumber = ceil($number / 10) * 10;
$roundedNumber = floor($number / 10) * 10;

echo str_pad('27', 4, "0", STR_PAD_LEFT); //0027
echo str_pad('12', 3, "0", STR_PAD_LEFT); //012
echo str_pad('5', 2, "0", STR_PAD_LEFT); //05

$text = 'This is my text';
echo $text[0]; //output: 'T'

//use substr
echo substr($string, 0, 1); //output: 'T'
//use mb_substr
$text = 'ê123ë';
echo mb_substr($text, 0, 1, "UTF-8"); //output: 'ê'

$string = 'PHP is a versatile scripting language that can be used for web development, system administration, and even game development.';
$chars_array = str_split($string);
foreach ($chars_array as $key => $char) {
	echo $char.'<br>';
}

$source = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; 
$source = str_shuffle($source);
$length = 8;
$randomString = substr($source,  0, $length);

$fruit = 'apple,orange,banana,pear';
$fruit_array = explode(',', $fruit);


$color = 'red|green|blue';
$color_array = split('\|', $color); 

$str = 'This #string has some @non-alphanumeric characters!';
$str = preg_replace('/[^a-zA-Z0-9]/i', '', $str);
echo $str; // Thisstringhassomenonalphanumericcharacters

$html = 'Welcome, <b>Peter</b><br />Profile';
$output = strip_tags($html, '<br>'); // 'Welcome, Peter<br />Profile'

$text = 'Parenthesis can be used to add friendly comments or asides. They can also be used to (emphasize information) or to set off additional information that might otherwise be disruptive.';
preg_match('#\((.*?)\)#', $text, $matches);
print $matches[1];

$text = 'These [brackets] are used to indicate something is optional.';
preg_match('#\[(.*?)\]#', $text, $matches);
foreach ($matches as $key => $match) {
    print $match.'<br/>';
}

function someFunction() {
  var xmlhttp = new XMLHttpRequest();
    xmlhttp.onreadystatechange = function() {
      if (this.readyState == 4 && this.status == 200) {
        document.querySelectorAll(".result")[0].innerText = this.responseText;
      }
    };
    xmlhttp.open("GET", "some_file.php", true);
    xmlhttp.send();
}
setInterval("someFunction", 10000);

define("GREETING", "Hello world!");
echo GREETING; //"Hello world!"

define("WEB_ROOT", "https://tleapps.com/");
echo "The URL is ".WEB_ROOT;

//command line
php -v

//PHP methods and constant
phpinfo();
echo 'My PHP version is: '.phpversion();
echo PHP_VERSION;

//user global keyword
$x = 5;

function myTest() {
    global $x;
    echo "<p>Variable x inside function is: $x</p>";
} 

//use $GLOBALS
$x = 5;
$y = 10;

function sum() {
    $GLOBALS['y'] = $GLOBALS['x'] + $GLOBALS['y'];
} 

sum();

echo $y; // Outputs 15
myTest();