Get Order ID in Custom Module

Question

First i make the custom module to add custom button in Order View page and its successfully added. Now i want to get the Current Order ID at my Custom Module Page. Please guide me how can i get the Current Order ID.

Basically i want to take the current order id by using query string to my next page.

Please let me know how can i get the order id at my next page?

code

addbuttoninorder($event) { 
     Mage::log("adadadasd"); 
     $block = $event->getBlock(); 
     $url = "exportleftovers.co/leopardmagento/…;; 
    if ($block instanceof Mage_Adminhtml_Block_Sales_Order_View) {
    $block->addButton('change_status', array( 
      'label' => Mage::helper('sales')->__('Leopard TN New'),      
      // 'onclick' => "confirmSetLocation('{$message}','{$block->getUrl('modulename/path/')}')", 
      'onclick' => "window.open('".$url."')", 'class' => 'go' ));
  } 

Answer 1

if you have query string like : www.DOMAIN.com/MODULENAME/CONTROLLER/ACTION/order_id/52

then you can get order_id from query srting by $this->getRequest()->getParam("order_id");

Update: For Observer.php, you can use

Mage::app()->getFrontController()->getRequest()->getParams();

or

Mage::app()->getRequest()->getParams()