bind webservice to gridview

hello,
I m stuck with 1 problem
i want to bind webservice to gridview 1 simple select query from employee table as user start typing in textbox the gridview should fill with relevent data without postback like "select employee_name from employee where employee_name like *** %"  its like binding  autocomplete extender to gridview with context key to textbox but still i am not getting how i'll achieve this 
some suggestions..
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