I don t know about C++ but there s how PHP works about:

For Function scopes:

<?php

  $b = 6;

  function testFunc($a){
    echo $a. - .$b;
  }

  function testFunc2($a){
    global $b;
    echo $a. - .$b;
  }

  testFunc(3);
  testFunc2(3);

?>

The output is

3-
3-6

Code inside functions can only be accessed variables outside functions using the global keyword. See http://php.net/manual/en/language.variables.scope.php

As for classes:

<?php

class ExampleClass{

  private $private_var = 40;
  public $public_var = 20;
  public static $static_var = 50;

  private function classFuncOne(){
    echo $this->private_var. - .$this->public_var; // outputs class variables
  }

  public function classFuncTwo(){
    $this->classFuncOne();
    echo $private_var. - .$public_var; // outputs local variable, not class variable
  }

}

$myobj = new ExampleClass();

$myobj->classFuncTwo();
echo ExampleClass::$static_var;
$myobj->classFuncOne(); // fatal error occurs because method is private

?>

Output would be:

40-20
-
50
Fatal error: Call to private method ExampleClass::classFuncOne() from context in C:xampphtdocsscope.php on line 22

One note to take: PHP does not have variable initialization, although variables are said to be set or not set. When a variable is set, it has been assigned with a value. You can use the unset to remove the variable and its value. A not set variable is equivalent to false, and if you use it with all errors output, you will see a E_NOTICE error.

In PHP there are static, local, private, public, and protected class variables.

However, in the PHP OOP implementation things are a little different: the manual will help you:

The visibility of a property or method can be defined by prefixing the declaration with the keywords public, protected or private.

Furthermore, have a look at the static keyword documentation.

You ll be able to read more about normal variables and their scope here: http://php.net/manual/en/language.variables.scope.php:

For the most part all PHP variables only have a single scope.

I hope the links will be able to explain it to you better than I did ;-)

yes, PHP 5 incldude static variables and visibility in class.

class MyClass
{
    public static $my_static =  foo ;
    public $public =  Public ;
    protected $protected =  Protected ;
    private $private =  Private ;

    public function staticValue() {
       return self::$my_static;
    }
    function printHello()
    {
        echo $this->public;
        echo $this->protected;
        echo $this->private;
    }
}

$obj = new MyClass();
echo $obj->public; // Works
echo $obj->protected; // Fatal Error
echo $obj->private; // Fatal Error
$obj->printHello(); // Shows Public, Protected and Private