Delete -- remove magento background data ----

Implement this method in Grid:
Protected function _ preparemassaction ()
{
$ This-> setmassactionidfield ('Post _ id ');
$ This-> getmassactionblock ()-> setformfieldname ('blog ');

$ This-> getmassactionblock ()-> additem ('delete', array (
'Label' => Mage: helper ('gao')->__ ('delete '),
'Url' => $ this-> geturl ('*/massdelete '),
'Confirm' => Mage: helper ('gao')->__ ('Are you sure? ')
));

$ Statuses = Mage: getsingleton ('blog/status')-> getoptionarray ();

Array_unshift ($ statuses, array ('label' => '', 'value' => ''));
$ This-> getmassactionblock ()-> additem ('status', array (
'Label' => Mage: helper ('blog ')->__ ('change status '),
'Url' => $ this-> geturl ('*/massstatus', array (' _ current' => true )),
'Additional' => array (
'Visibility '=> array (
'Name' => 'status ',
'Type' => 'select ',
'Class' => 'required-entry ',
'Label' => Mage: helper ('blog ')->__ ('status '),
'Values' => $ statuses
)
)
));
Return $ this;
}