c# – ViewModel在HttpPost方法中为Null

public class NotificationViewModel
{

    public string GroupDesc { get; set; }

    public bool AM { get; set; }

    public bool PM { get; set; }

    public int MaxNotif { get; set; }
}

public class SettingsViewModel
{
    public List<NotificationViewModel> ListNotification { get; set; }

    public SettingsViewModel()
    {
        ListNotification = new List<NotificationViewModel>();
    }
}

我的看法 ：

@model PortailT2A.Models.SettingsViewModel

@{
    ViewBag.Title = "Preferences";
    Layout = "~/Views/Shared/_LayoutAdmin.cshtml";
}

<h2>Preferences</h2>


@using(Html.BeginForm("Preferences","Administrateur",FormMethod.Post))
{

    <table id="settingsTable">
        <tr>
            <th>Groupe</th>
            <th></th>
            <th>AM</th>
            <th>PM</th>
            <th>Limite de notifications</th>
        </tr>

    @for (int i = 0; i < Model.ListNotification.Count(); i++ )
    {
        var notif = Model.ListNotification[i];
        <tr>
            <td>@notif.GroupDesc </td>
            <td>Heure de notification</td>
            <td>@Html.CheckBoxFor(u => notif.AM)  </td>
            <td>@Html.CheckBoxFor(u => notif.PM)  </td>
            <td>@Html.TextBoxFor(u => notif.MaxNotif)</td>
        </tr>
        <tr/>


    }

    </table>


    <input type ="submit" value="Sauvegarder" />

}

我的HttpGet方法填充我的ViewModel并返回它.

[HttpGet]
    public ActionResult Preferences(long idUser)
    {
        context = new MainDatabaseEntities();

        List<NotificationViewModel> notifications = new List<NotificationViewModel>();

        SettingsViewModel settings = new SettingsViewModel();

        //Population...

        return View(settings);
    }

但是,当我想保存更改时,我得到一个nullM的ViewModel,我不明白为什么.伙计们好吗？

编辑：我的帖子方法：

[HttpPost]
            public ActionResult Preferences(SettingsViewModel sm)
            {
                //since here my ViewModel is null
                context = new MainDatabaseEntities();

                Utilisateur user = (from u in context.Utilisateurs where u.Username == User.Identity.Name select u).FirstOrDefault();

                //operations...

}

生成的HTML：

<tr>
        <td>Groupe B </td>
        <td>Heure de notification</td>
        <td><input id="notif_AM" name="notif.AM" type="checkbox" value="true" /><input name="notif.AM" type="hidden" value="false" />  </td>
        <td><input checked="checked" id="notif_PM" name="notif.PM" type="checkbox" value="true" /><input name="notif.PM" type="hidden" value="false" />  </td>
        <td><input id="notif_MaxNotif" name="notif.MaxNotif" type="text" value="10" /></td>
    </tr>