instead of commandfield, try using like
<asp:TemplateField HeaderText="Action" HeaderStyle-Width="20%" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<asp:LinkButton ID="LnkManageTitle" runat="server" Text="Manage Title" CommandName="Edit"></asp:LinkButton>
</ItemTemplate>
<EditItemTemplate>
<asp:LinkButton ID="LnkManageTitle" runat="server" Text="Save" CommandName="Update"></asp:LinkButton>
</EditItemTemplate>
</asp:TemplateField>
rest seems to be fine.
For Updating, Call OnRowUpdating="Gridview1_RowUpdating"
on html page and on CS page declare an event.
Protected Void Gridview1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
}
Don't forget to call CommandName="Update"
on a LinkButton