displaying dropdownlist selected data in the Gridview using the objecy datasource

[mr.smiley]

hello all
i got some list of services(ex:hotels,restaurents etc) in my dropdown list which i had taken from the data source object. when an service is selected the information about the service must be displayed in the grid view box(eglace,contact,etc).i had already taken grid viewbox to display all my services and the information about it in which it is using another data source object.my question is if any item from the dropdown listbox is selected the information about that must be displayed in the gridview box.

please can one help me out with an example or code

thanks in advance..