In this post How to Delete Data From ObjecctDataSource in Asp.net

public DataSet GetCustomerDetail( )
{
String constring = "Data Source=sk-Pc; Initial Catalog=customerdatabase; Integrated Security=true";
SqlConnection sqlcon = new SqlConnection(constring);
String query = "select * from customerdetail";
SqlCommand sqlcmd = new SqlCommand();
sqlcmd.CommandText = query;
sqlcmd.Connection = sqlcon;
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = sqlcmd;
DataSet ds = new DataSet();
da.Fill(ds);
return ds;
}

public void deleteCustomerDetail(int customerid)
{
String constring = "Data Source=sk-pc; Initial Catalog=customerdatabase; Integrated Security=true";
SqlConnection sqlcon = new SqlConnection(constring);
SqlCommand sqlcmd = new SqlCommand("delete from customerdetail where customerid=" + customerid, sqlcon);
sqlcon.Open();
sqlcmd.ExecuteNonQuery();
sqlcon.Close();
}