Example of a PHP static variable

Class Test
{
public static function A () {}
Public Function B () {}
}
$obj = new test;

Calling code

Test::a ();
$obj->a ();
$obj->b ();

Examples of examples that require static variables
<?php Tutorials

Class MyObject {
public static $mystaticvar = 0;

function MyMethod () {
:: Scoping operators for scopes
Use the self scope instead of the $this scope
Because $this represents only the current instance of the class, and self:: The expression is the class itself
Self:: $mystaticvar + = 2;
echo Self:: $mystaticvar. "<br/>";
}
}

$instance 1 = new MyObject ();
$instance 1->mymethod (); Showing 2

$instance 2 = new MyObject ();
$instance 2->mymethod (); Showing 4

?>

<?php

Class MyObject {
public static $myvar = 10;
}

echo MyObject:: $myvar;

Results: 10
?>

This function is of little use because the value of $w 3sky is set to 0 and output "0" each time it is called. Adding a variable to a $w 3sky++ has no effect, because once you exit this function, the variable $w 3sky does not exist. To write a count function (www.111cn.net) that does not lose this count value, define the variable $w 3sky as static:

Examples of using static variables

<?php
function test ()
{
static $w 3sky = 0;
echo $w 3sky;
$w 3sky++;
}
?>
Now, each call to the test () function outputs the value of $w 3sky and adds one.

See an example

<?php
Class Foo
{
public static $my _static = ' foo ';
Public Function Staticvalue () {
Return self:: $my _static;
}
}
Class Bar extends Foo
{
Public Function foostatic () {
Return Parent:: $my _static;
}
}
Print foo:: $my _static. "N";
$foo = new Foo ();
Print $foo->staticvalue (). "N";
Print $foo->my_static. "N"; Undefined "Property" my_static
Print $foo:: $my _static. "N";
$classname = ' Foo ';
Print $classname:: $my _static. "N"; PHP 5.3.0 can be dynamically called after
Print bar:: $my _static. "N";
$bar = new Bar ();
Print $bar->foostatic (). "N";
?>

From:http://www.111cn.net/phper/php/php-static.htm

Example of a PHP static variable