asp.net-mvc – MVC中的绑定集合

我有一个View Model,它由Applicant对象和TeamMember集合组成.当我发布模型时,Team集合始终为null.我已经尝试将我的原始IEnumarable中的集合更改为List但这并没有什么区别.所以我更改了控制器编辑操作以接受FormCollection,并验证了viewModel [“member.FirstName”]中有数据.我迷失了为什么绑定不起作用.我试图尽可能地清理我的代码示例,但我对我所缺少的内容感到困惑.任何帮助是极大的赞赏！

查看模型属性

public class MyViewModel
{
    public Applicant ApplicantInfo { get; set; }
    public List<TeamMember> TeamMembers { get; set; }
}

调节器

[HttpPost]
public ActionResult Edit(MyViewModel viewModel)
{
         //  viewModel.ApplicantInfo has the form data
         //  viewModel.TeamMembers = null              
}

视图

<% using (Html.BeginForm())
       {%>
    <h3>
    <a href="#">Applicant Information</a>
    </h3>
    <label>
        City
        <%: Html.TextBoxFor(m => Model.ApplicantInfo.City)%>
    </label>
    <label>
        State
        <%: Html.TextBoxFor(m => Model.ApplicantInfo.State)%>
    </label>

    <h3>
    <a href="#">Team</a>
    </h3>
    <div>
    <% foreach (var member in Model.TeamMembers)
    { %>           
    <div class="editor-field">
        <%: Html.DropDownList("member.Type",Model.GetMemberTypes(member.MemberType.TypeId))%>
    </div>
    <div class="editor-field">
        <%: Html.EditorFor(m => member.FirstName)%>
    </div>
    <div class="editor-field">
        <%: Html.EditorFor(m => member.LastName)%>
    </div>
    <div class="editor-field">
        <%: Html.EditorFor(m => member.Title)%>
    </div>            
    <%} %>
    </div>
    <p>
        <input type="submit" value="Save" />
    </p>
    <% } %>

<% for (int i=0; i<Model.TeamMembers.Count; i++) { %>
<div class="editor-field">
  <%: Html.EditorFor(m => m.TeamMembers[i].FirstName)%>
</div>
<div class="editor-field">
  <%: Html.EditorFor(m => m.TeamMembers[i].LastName)%>
</div>
<% } %>

<% foreach (var member in Model.TeamMembers) { %>
  <%: Html.EditorFor(x => 
    member,"TeamMember","TeamMembers["+(member.Number-1)+"]",new { MemberTypes = Model.GetMemberTypes(member.MemberType.TypeId) })%>
<% } %>