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Bilal Niaz
Bilal Niaz

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PHP Data Types:

PHP Data Types:
Variables can store data of different types, and different data types can do different things.
PHP supports the following data types:

  • String
  • Integer
  • Float (floating point numbers - also called double)
  • Boolean
  • Array
  • Object
  • NULL
  • Resource PHP String: A string is a sequence of characters, like "Hello world!". A string can be any text inside quotes. You can use single or double quotes:
<?php
$x = "Hello world!";
$y = 'Hello world!';

echo $x;
echo "<br>";
echo $y;
?>
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PHP Integer:
An integer data type is a non-decimal number between -2,147,483,648 and 2,147,483,647.
Rules of integer:

  • An integer must have at least one digit
  • An integer must not have a decimal point
  • An integer can be either positive or negative
  • Integers can be specified in: decimal (base 10), hexadecimal (base 16), octal (base 8), or binary (base 2) notation. In the following example $x is an integer. The PHP var_dump() function returns the data type and value:
<?php
$x = 5985;
var_dump($x);
?>
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PHP Float:
A float (floating point number) is a number with a decimal point or a number in exponential form.
In the following example $x is a float. The PHP var_dump() function returns the data type and value

<?php
$x = 10.365;
var_dump($x);
?>
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PHP Boolean:
A Boolean represents two possible states: TRUE or FALSE.
Booleans are often used in conditional testing. You will learn more about conditional testing in a later chapter of this tutorial.

$x = true;
$y = false;
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PHP Array:
An array stores multiple values in one single variable.

<?php
$cars = array("Volvo","BMW","Toyota");
var_dump($cars);
?>
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PHP Object:
Classes and objects are the two main aspects of object-oriented programming.
A class is a template for objects, and an object is an instance of a class.
When the individual objects are created, they inherit all the properties and behaviors from the class, but each object will have different values for the properties.

class Car {
  public $color;
  public $model;
  public function __construct($color, $model) {
    $this->color = $color;
    $this->model = $model;
  }
  public function message() {
    return "My car is a " . $this->color . " " . $this->model . "!";
  }
}

$myCar = new Car("black", "Volvo");
echo $myCar -> message();
echo "<br>";
$myCar = new Car("red", "Toyota");
echo $myCar -> message();
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PHP NULL Value:
Null is a special data type which can have only one value: NULL.
A variable of data type NULL is a variable that has no value assigned to it.

$x = "Hello world!";
$x = null;
var_dump($x);
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PHP Resource:
The special resource type is not an actual data type. It is the storing of a reference to functions and resources external to PHP.
A common example of using the resource data type is a database call.

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