PHP Data types

DATATYPES IN PHP

Data Types: Data types defines the type of values a variable can store.

PHP supports the following data types:
·         String
·         Integer
·         Float (floating point numbers - also called double)
·         Boolean
·         Array
·         Object
·         NULL

String : A string is a collection of characters, like "Hi guys".
We use quotes(" ") to define a string. We can use single or double quotes:

Example:
$q = "Hi guys !";
$w = 'Keep smiling';
echo $q;
echo "
";
echo $w;
?>

OUTPUT:
Hi guys!
Keep smiling

Integer: An integer data type is a non-decimal number between -2,147,483,648 and 2,147,483,647.It stores integer type of values.

Rules for integers:
·         An integer must have at least one digit
·         An integer must not have a decimal point
·         An integer can be either positive or negative

Example
$a= 57
var_dump($a);
?>

OUTPUT:
int(57)
In the above $a is an integer. The PHP var_dump() function returns the data type and value:

Float: A float (floating point number) is a  number in the exponential form.
In the following example $x is a float. The PHP var_dump() function returns the data type and value:

Example
$x = 1.35;
var_dump($x);
?>

Output:
1.35

Boolean: A Boolean represents two possible states: TRUE or FALSE.
$A = true;
$B = false;
Booleans are used for conditional testing.

Array: An array is a type of container that stores multiple values in one single variable in contigous memory allocation.

Example
$flower = array("Lilly","Rose","Lotus");
var_dump($flower);
?>

OUTPUT:
array(3) { [0]=> string(5) "Lilly" [1]=> string(3) "Rose" [2]=> string(6) "Lotus" }
In the above example $flower is an array. The PHP var_dump() function returns the data type and value.

Object: An object is a data type which stores data and information on how to process that data.
Object is an entity that reflects real world objects.

Rules to declare Object:
·         In PHP, an object must be explicitly declared.
·         we must declare a class of object. For this, we use the class keyword. A class is a structure that can contain properties and methods.


Example
class Flower{
function Flower() {
    $this->model = "Lotus";
}
}
// create an object
$obj = new Flower();
// show object properties
echo $obj->model;
?>

OUTPUT:
Lotus

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.
By default, a variable is of NULL data type if no value is assigned to it.
Variables can also be emptied by setting the value to NULL

Example:
$a = "Hi guys!";
$a = null;
var_dump($a);
?>

OUTPUT:
NULL

Content writer:
Er. Khushi Jain
CSE 6th Sem
TSPC, Burhanpur

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