PHP Scope, Static and Constants

Variables created inside a function are local. Use global to reach a global one, static to keep a value between calls, and define/const for constants.

ExamplePHP

<?php
$x = 10;

function noAccess() {
  return isset($x) ? "sees x" : "no x here";
}
function withGlobal() {
  global $x;
  return $x + 1;
}
function counter() {
  static $n = 0;
  return ++$n;
}

echo noAccess(), "\n";
echo withGlobal(), "\n";
echo counter(), counter(), counter(), "\n";

define("SITE", "WeCode");
const VERSION = "1.0";
echo SITE, " ", VERSION, "\n";
echo defined("SITE") ? "defined" : "missing", "\n";

Output

no x here
11
123
WeCode 1.0
defined

Quick check

What does static do to a variable inside a function?

Keeps its value between callsMakes it globalMakes it constant

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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