How Do I Customize It This Commandname="Login" In Cs Code?

<asp:Login runat="server" ViewStateMode="Disabled" RenderOuterTable="false">
            <LayoutTemplate>
                <p class="validation-summary-errors">
                    <asp:Literal runat="server" ID="FailureText" />
                </p>
                <fieldset>
                    <legend>Log in Form</legend>
                    <ol>
                        <li>
                            <asp:Label runat="server" AssociatedControlID="UserName">User name</asp:Label>
                            <asp:TextBox runat="server" ID="UserName" />
                            <asp:RequiredFieldValidator runat="server" ControlToValidate="UserName" CssClass="field-validation-error" ErrorMessage="The user name field is required." />
                        </li>
                        <li>
                            <asp:Label runat="server" AssociatedControlID="Password">Password</asp:Label>
                            <asp:TextBox runat="server" ID="Password" TextMode="Password" />
                            <asp:RequiredFieldValidator runat="server" ControlToValidate="Password" CssClass="field-validation-error" ErrorMessage="The password field is required." />
                        </li>
                        <li>
                            <asp:CheckBox runat="server" ID="RememberMe" />
                            <asp:Label runat="server" AssociatedControlID="RememberMe" CssClass="checkbox">Remember me?</asp:Label>
                        </li>
                    </ol>
                        <asp:Button runat="server" CommandName="Login" Text="Log in" />
                </fieldset>
            </LayoutTemplate>
        </asp:Login>