get value of templatefield in gridview

Question

how to get value from eval itemtemplat ? have a look on below my code

 <asp:TemplateField HeaderText="Estimated Cost">
                            <ItemTemplate>
                                <%# Eval("EstimatedCost")%>
                            </ItemTemplate>
                        </asp:TemplateField>
i want to get EstimatedCost to one string