Email Binding in Asp.Net GridView

<asp:TemplateField HeaderText="Email">

                        <ItemTemplate>

                            <asp:HyperLink runat="server" ID="HyperLink1" NavigateUrl='<%# string.Format("mailto:{0}", Eval("Email")) %>'

                                Text='<%# Eval("Email") %>' />

                        </ItemTemplate>

                        

                    </asp:TemplateField>