Forms Data Controls :: How To Count Total Record In Data Grid And Export To Excel

how to count total record in my data grid and after that export the records to excel ?

Below are the coding of my datagrid .

GridView id="grdCustomer"
void Data()
{
qry = "select * from customer order by customerId DESC";
DataSet ds = new DataSet();
ds = DBUtil.getTable(qry);
if (ds.Tables[0].Rows.Count != 0)
{
grdCustomer.DataSource = ds;
grdCustomer.DataBind();
}
else
{
lblMsg.Text = "Customer List Is Empty";
}
}