PHP OOP - Static Properties
PHP - Static Properties
The
static keyword is used to create static
properties.
Static properties can be accessed directly - without creating an instance of a class first.
Declare a Static Property
To declare a static property in a class, use the
static
keyword:
class ClassName {
public static $statProp = "W3Schools";
}Access a Static Property
To access a static property, specify the class name, followed by a double colon (::) and the method name:
ClassName::$statProp;In the following example, we declare a static property: $value. Then, we echo the value of the static property directly by using the class name, double colon (::), and the property name (without creating a class first):
Example
<?php
class
pi {
// static property
public static $value = 3.14159;
}
// Get static property directly
echo pi::$value;
?>
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PHP - More on Static Properties
A class can have both static and non-static properties. A static property can be
accessed from a method in the same class using the self
keyword and double colon (::):
Example
<?php
class
pi {
public static $value=3.14159;
public function
staticValue() {
return self::$value;
}
}
$pi = new pi();
echo $pi->staticValue();
?>
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To call a static property from a child class, use the parent
keyword inside the child class:
Example
<?php
class
pi {
public static $value=3.14159;
}
class x extends pi {
public function xStatic() {
return
parent::$value;
}
}
// Get value of static property
directly via child class
echo x::$value;
// or get value of static property via xStatic()
method
$x = new x();
echo $x->xStatic();
?>
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