How to add filter criteria to excel sheet through coding in c#?

Hi ,
The code below is how i generate the excel sheet and pass the data that i get in String builder(sb).
I want to apply filter criteria to it.
So please anyone help me out.



Response.Clear();
Response.Charset = string.Empty;
Response.ContentType = "application/ms-excel";
Response.AddHeader("content-disposition", "attachment;filename=" + "EventExcelReport" + ".xls");
Response.Write(sb.ToString());
Response.End();