03-Apr-2023
.
Admin
Hi guys,
Today i will explained how to use php Global Variables and Superglobals. This example is so easy to use in php.
Superglobals were introduced in PHP 4.1.0, and are built-in variables that are always available in all scopes.
Some predefined variables in PHP are "superglobals", which means that they are always accessible, regardless of scope - and you can access them from any function, class or file without having to do anything special.
So let's start to the example.
The PHP superglobal variables are:
$GLOBALS
$_SERVER
$_REQUEST
$_POST
$_GET
$_FILES
$_ENV
$_COOKIE
$_SESSION
$GLOBALS
$GLOBALS is a PHP super global variable which is used to access global variables from anywhere in the PHP script.
<!DOCTYPE html>
<html>
<body>
<?php
$x = 75;
$y = 25;
function addition() {
$GLOBALS['z'] = $GLOBALS['x'] + $GLOBALS['y'];
}
addition();
echo $z;
?>
</body>
</html>
Output
100
$_SERVER
$_SERVER is a PHP super global variable which holds information about headers, paths, and script locations.
<!DOCTYPE html>
<html>
<body>
<?php
echo $_SERVER['PHP_SELF'];
echo "<br>";
echo $_SERVER['SERVER_NAME'];
echo "<br>";
echo $_SERVER['HTTP_HOST'];
echo "<br>";
echo $_SERVER['HTTP_REFERER'];
echo "<br>";
echo $_SERVER['HTTP_USER_AGENT'];
echo "<br>";
echo $_SERVER['SCRIPT_NAME'];
?>
</body>
</html>
Output
/demo/demo_global_server.php
35.194.26.41
35.194.26.41
https://tryphp.w3schools.com/showphp.php?filename=demo_global_server
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:90.0) Gecko/20100101 Firefox/90.0
/demo/demo_global_server.php
$_REQUEST
PHP $_REQUEST is a PHP super global variable which is used to collect data after submitting an HTML form.
<!DOCTYPE html>
<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type="text" name="fname">
<input type="submit">
</form>
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
// collect value of input field
$name = $_REQUEST['fname'];
if (empty($name)) {
echo "Name is empty";
} else {
echo $name;
}
}
?>
</body>
</html>
Output
abc
$_POST
PHP $_POST is a PHP super global variable which is used to collect form data after submitting an HTML form with method="post". $_POST is also widely used to pass variables.
<!DOCTYPE html>
<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type="text" name="fname">
<input type="submit">
</form>
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
// collect value of input field
$name = $_REQUEST['fname'];
if (empty($name)) {
echo "Name is empty";
} else {
echo $name;
}
}
?>
</body>
</html>
Output
abc
$_GET
PHP $_GET is a PHP super global variable which is used to collect form data after submitting an HTML form with method="get".
$_GET can also collect data sent in the URL.
<!DOCTYPE html>
<html>
<body>
<a href="test_get.php?subject=PHP&web=W3schools.com">Click $GET</a>
</body>
</html>
Output
Click $GET
Now you can check your own.
I hope it can help you...
#PHP 8
#PHP