How do variables work in PHP?
Variables are assigned in a typical manner. Normal variables are preceded with a $ and assigned to with =. Any variable can be used in an array by including a key in square brackets after the variable.
For a regular array, a number is used as the key.
For an associative array, a quotes enclosed string (or another variable) is used.
The function ‘array’ can also be used to create arrays of either type.
The code below illustrates these features (lines beginning with “//” are comments):
// Normal variable assignment
$person = "Bob";
// Assigning to a regular array
$fruit[0] = "apple";
$fruit[1] = "grape";
$fruit[2] = "orange";
// Assigning to an associative array
$mother['kitten'] = "cat";
$mother['puppy'] = "dog";
// Using the array function for a regular array
$fruit = array('apple','grape','orange');
// Using the array function for an associative array
$mother = array('kitten' => 'cat', 'puppy' => 'dog');
// The following line prints "Bob's cat ate an orange."
echo "$person's $mother['kitten'] ate an $fruit[2].";
?>
One of the most powerful features of PHP is its easy access to requested variables. For instance, consider the following short form:
<form action="form_handler.php?posted=true" method="post">
<input name="formvar">
<input value="Submit Query" type="submit">
</form>
On submitting the form, the value of the variable “formvar” will be available to the form_handler.php script simply as
$_POST['formvar']
and the variable posted simply
$_GET['posted'].
This is true for all POST and GET form calls.