要作为IEnumerable <httppostedfilebase>上载的多个文件的列表

Question

我想在动态表单列表中上传多个文件。我的模型就像

class mymodel
{
    public IEnumerable<FileAttachmentViewModel> FileAttachments { get; set; }
}

public class FileAttachmentViewModel
{
    [DataType(DataType.Upload)]
    public IEnumerable<HttpPostedFileBase> files { get; set; }
    public bool IsPrivate { get; set; }
    public string Description { get; set; }
}

但是我的控制器会为文件

返回null

我的观点

<div class="panel panel-default">
    <div class="panel-heading">
        File 1
        <button type="button" style="margin-bottom:10px;" class='pull-right btn btn-success add-file'><span class="glyphicon glyphicon-plus"></span>Add File </button>
    </div>
    <div class="panel-body">
        <div class="form-group">
            <label class="label-control col-md-3"> Select File </label>
            <input type="file" class="form-control col-md-4" name="FileAttachments[0][files]" multiple="multiple" />
            <label class="label-control col-md-2"> IsPrivate </label>
            <input type="checkbox" name="FileAttachments[0][IsPrivate]" class="col-md-3" value="true">
        </div>
        <div class="form-group">
            <label class="label-control col-md-3"> Description </label>
            <textarea name="FileAttachments[0][Description]" class="form-control col-md-9"></textarea>
        </div>
    </div>
</div>
<div id="fileupload"></div>

使用javascript进行动态查看。 和我的控制器

public ActionResut Register(myviewmodel model)
{
    if (model.FileAttachments != null)
    {
        foreach (var att in model.FileAttachments)
        {
            if (att.files != null)
            {
                foreach (HttpPostedFileBase file in att.file)
                {
                    var fileName = Path.GetFileName(file.FileName);
                    attachment = new Attachment();
                    attachment.AttachmentId = Guid.NewGuid();
                    attachment.Description = att.Description;
                    attachment.URL = "~/Content/Heritage/Attachments/" + fileName;
                    attachment.Type = file.ContentType;
                    attachment.HeritageId = heritage.HeritageId;
                    //attachment.OtherType = model.OtherType;
                    attachment.IsPrivate = att.IsPrivate;
                    _AttachmentService.Insert(attachment);
                    file.SaveAs(Path.Combine(Server.MapPath("~/Content/Heritage/Attachments/" + fileName)));
                }
            }
        }
    }
}