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    <p>You are creating a "<code>sam</code>" object by "<code>new sam</code>", you sould use "<code>sam::getInstance()</code>"; to reach the static instance but it won't be "sam object" type will be "Singleton" "."<strong>__<em>CLASS</em>__</strong>" gives the scope class not the real object class.</p> <p><strong>First</strong>: you must read about "<a href="http://php.net/manual/en/language.oop5.late-static-bindings.php" rel="nofollow">late static binding</a>" in php and learn the limitations of self:: and <strong>__<em>CLASS</em>__</strong> use "<code>static::</code>" instead of "<code>self::</code>" (5.3+)</p> <p>Or you can change all the pattern use statics like;</p> <pre><code> &lt;?php class Singleton { // A static property to hold the single instance of the class private static $instance; // The constructor is private so that outside code cannot instantiate public function __construct() { } // All code that needs to get and instance of the class should call // this function like so: $db = Database::getInstance(); public static function getInstance() { // If there is no instance, create one if (!isset(self::$instance)) { $c = __CLASS__; self::$instance = new $c; } return self::$instance; } // Block the clone method private function __clone() {} // Function for inserting data to object public function insertData($param, $element) { $this-&gt;{$param} = $element; } } //---CLASS ram--- class ram { function __construct() { $db = Singleton::getInstance(); $db-&gt;insertData('name', 'Suresh'); } } $obj_ram = new ram; //---CLASS sam--- class sam extends Singleton { function __construct() { parent::__construct(); } public static function show_data() { echo "&lt;br&gt;Data in current object&lt;br&gt;"; print_r(self::getInstance()); echo "&lt;br&gt;&lt;br&gt;Data in singleton object&lt;br&gt;"; $singleton_obj = Singleton::getInstance(); print_r($singleton_obj); } } $obj_sam = sam::getInstance(); print_r($obj_sam); echo sam::show_data(); </code></pre> <p>This is an example which setting the properties pointers to the current object like "CI"</p> <pre><code>&lt;?php class Singleton { // A static property to hold the single instance of the class private static $instance; // The constructor is private so that outside code cannot instantiate public function __construct() { if(isset(self::$instance)) foreach(self::$instance as $key =&gt; &amp;$val) { $this-&gt;{$key} = &amp;$val; } } // All code that needs to get and instance of the class should call // this function like so: $db = Database::getInstance(); public static function getInstance() { // If there is no instance, create one if (!isset(self::$instance)) { $c = __CLASS__; self::$instance = new $c; } return self::$instance; } // Block the clone method private function __clone() {} // Function for inserting data to object public function insertData($param, $element) { $this-&gt;{$param} = $element; } } //---CLASS ram--- class ram { function __construct() { $db = Singleton::getInstance(); $db-&gt;insertData('name', 'Suresh'); } } class ram2 { function __construct() { $db = Singleton::getInstance(); $db-&gt;insertData('name', 'Suresh'); $db-&gt;insertData('name2', 'Suresh2'); } } $obj_ram = new ram; $obj_ram = new ram2; //---CLASS sam--- class sam extends Singleton { function __construct() { parent::__construct(); } public function show_data() { echo "&lt;br&gt;Data in current object&lt;br&gt;"; print_r($this); echo "&lt;br&gt;&lt;br&gt;Data in singleton object&lt;br&gt;"; $singleton_obj = Singleton::getInstance(); print_r($singleton_obj); } } $obj_sam = new sam; echo $obj_sam-&gt;show_data(); </code></pre>
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    1. COHey, thanks a lot for helping me by showing exact code. This is really helpful. Can u tell me, is there any mechanistic by which in show_data() of 'sam' class.. i can get all the data of singleton object by using $this. Ex : print_r($this) : // Should give all singleton object data
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    2. COif you want to use "$this" you must write your code into Singleton class because the type of "$instance" is "Singleton". Why arent you using "Singleton::getInstnace()" if you want the Singleton object properties?
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    3. COHey, I'm not so good in PHP OOP's. Can u help me by showing some code. I mean, what.. exactly i need to write in singleton class. So that, in in show_data() of 'sam' class i can get those data by $this.
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