PHP Cheat Sheet (DRAFT) by Syshella

function greeting($value = "Sam") // Default value = Sam
{
    return "Hello $value!";
}

$return_value = greeting("Tom");

echo $return_value; //Prints: Hello Tom!
echo greeting(); //Prints: Hello Sam!

function addXPermanently (&$param) // Passed by reference
{
  $param = $param . "X";
  echo $param;
};
$word = "Hello";
addXPermanently($word); // Prints: HelloX
echo $word; // Prints: HelloX

Associative array
$my_array = ["panda" => "very cute", "lizard" => "cute", "cockroach" => "not very cute"];

Array function
$about_me = array(
    "fullname" => "Aisle Nevertell",
    "social" => 123456789
);

echo implode($my_array); // Prints only the values
print_r($my_array); // Prints keys and values

$my_array = ["new"] = "new item"; // Adds new element

$favorites = ["favorite_food"=>"pizza", "favorite_place"=>"my dreams", "FAVORITE_CASE"=>"CAPS", "favorite_person"=>"myself"];
 
echo  $favorites["favorite" . "_" . "food"]; 
// Prints: pizza
 
$key =  "favorite_place";
echo  $favorites[$key];  
// Prints: my dreams
 
echo $favorites[strtoupper("favorite_case")];
// Prints: CAPS

unset("my_array["new"]); // Delete the "new" element if exists

<?php
$lucky_number = 5 * 2 - 1;
 
echo "<h1>Your lucky number is ${lucky_number}</h1>";
?>


<?php
function makeHeaderGreeting ($name){
  return "<h1>Hello, ${name}!</h1>";
}
 
echo makeHeaderGreeting("World");
?>

$about_me = [
  "name" => "Aisle Nevertell",
  "birth_year" => 1902,
  "favorite_food" => "pizza"
];

function calculateAge ($person_arr){
  $current_year = date("Y");
  $age = $current_year - $person_arr["birth_year"];
  return $age;
}
?>
<h1>Welcome!</h1>
<h2>About me:</h2>
<?php   
  echo "<h3>Hello! I'm {$about_me["name"]}!</h3>";
  echo "<p> I'm " . calculateAge($about_me). " years old! That's pretty cool, right?</p>";
  echo "<div>What more is there to say? I love {$about_me["favorite_food"]}, and that's pretty much it!</div>";
?>