refresh parent grid on close of sp 2010 model dialog

Hi everybody,

subject : refresh parent grid on close of sp 2010 model dialog.

Generally we are placing multiple web parts in a share point page. Like that i also place custome web parts in my page. Those custome web parts are nothing but visual web parts. In that web parts i had gridview control from there I am opening a model dialog. when i closed that model dialog my requirement is to refresh gridview from where i open the model dialog. but not the whole page refresh.
Now my total page is refreshing when i close the webpart.

Thanks in advance.