• PHP all declared and environment variables can be listed
• get_defined_vars() method returns all the variables in the form of array.
• The array returned is handles by the class ArrayObject class.

<?php
    $name="roseindia";
    $city="new delhi";
    $arr1 = new ArrayObject(get_defined_vars());

    foreach ($arr1 as $key=>$val)
    echo"<br> key---->".$key." value------>".$val;
?>

Output
key---->GLOBALS value------>Array
key---->_ENV value------>Array
key---->HTTP_ENV_VARS value------>Array
key---->_POST value------>Array
key---->HTTP_POST_VARS value------>Array
key---->_GET value------>Array
key---->HTTP_GET_VARS value------>Array
key---->_COOKIE value------>Array
key---->HTTP_COOKIE_VARS value------>Array
key---->_SERVER value------>Array
key---->HTTP_SERVER_VARS value------>Array
key---->_FILES value------>Array
key---->HTTP_POST_FILES value------>Array
key---->_REQUEST value------>Array
key---->name value------>roseindia
key---->city value------>new delhi

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