Asp.net mvc 未保存所选内容的下拉列表

我是MVC新手。我使用DropDownListFor显示公司名称列表，并根据所做的选择填写其他客户字段。客户字段填充得很好，但是当我尝试发布记录时，我得到一个验证错误“需要公司名称”，即使在DropDownList for中选择了公司名称。以下是ViewModel：

     namespace CMSUsersAndRoles.Models
{
    public class QuoteViewModel
    {   [Key]
        [Display(Name = "Quote Id")]
        public int QuoteId { get; set; }
        // Columns from Customer table
        [Required(ErrorMessage = "Please select a company")]
        [Display(Name = "Customer Id")]
        public int? CustomerId { get; set; }
        [Display(Name = "Sales Rep")]
        public string SalesRep { get; set; }
        [Display(Name = "First Name")]
        public string FirstName { get; set; }
        [Display(Name = "Last Name")]
        public string LastName { get; set; }
        [Required]
        public string Company { get; set; }
        [Display(Name = "Address 1")]
        public string Address1 { get; set; }
        [Display(Name = "Address 2")]
        public string Address2 { get; set; }
        public string City { get; set; }
        public string State { get; set; }
        [StringLength(10)]
        [Display(Name = "Zip Code")]
        [RegularExpression(@"^\d{5}(-\d{4})?$", ErrorMessage = "Invalid Zip Code")]
        public string PostalCode { get; set; }
        [Phone]
        [Display(Name = "Work Phone")]
        public string WorkPhone { get; set; }
        [Phone]
        [Display(Name = "Cell Phone")]
        public string CellPhone { get; set; }
        [EmailAddress]
        public string Email { get; set; }
        [Range(0, 100)]
        public decimal? Discount { get; set; }
        [Display(Name = "Payment Terms")]
        public int? PaymentTerms { get; set; }
        // Columns from QuoteDetail table
        [Display(Name = "Quote Detail")]
        public List<QuoteDetail> QuoteDetail { get; set; }
        // Columns from Quote table


        public decimal Subtotal { get; set; }
        public decimal Tax { get; set; }
        public decimal Total { get; set; }
        [DataType(DataType.Date)]
        [Display(Name = "Quote Date")]
        public DateTime? QuoteDate { get; set; }
        [DataType(DataType.Date)]
        [Display(Name = "Good Until")]
        public DateTime? GoodUntil { get; set; }
        [DataType(DataType.Date)]
        [Display(Name = "Quote Sent")]
        public DateTime? QuoteSent { get; set; }
        [DataType(DataType.Date)]
        [Display(Name = "Date Approved")]
        public DateTime? DateApproved { get; set; }
        [DataType(DataType.Date)]
        [Display(Name = "Date Ordered")]
        public DateTime? DateOrdered { get; set; }

    }
}

以下是获得：

public ActionResult Create()
        {
            QuoteViewModel qvm = new QuoteViewModel();

            var customers = db.Customers.ToList();
            ViewBag.Customers = customers;

            return View(qvm);
        }

以下是该职位的代码：

[HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create(QuoteViewModel qvm)
{

if (ModelState.IsValid)
            { 
                Quote quote1 = new Quote();

                quote1.CustomerId = qvm.CustomerId;
                ...
                customer.CustomerId = (int)qvm.CustomerId;
                ...
                customer.Company = qvm.Company;    

                db.Entry(customer).State = EntityState.Modified;
                try
                    {
                        db.SaveChanges();
                    }
                    catch (DbUpdateConcurrencyException ex)
                    {

                        var objContext = ((IObjectContextAdapter)db).ObjectContext;
                        // Get failed entry
                        var entry = ex.Entries.Single();
                        // Now call refresh on ObjectContext
                        objContext.Refresh(RefreshMode.ClientWins, entry.Entity);


                    }


                return RedirectToAction("Index");
            }

            var customers = db.Customers.ToList();
            ViewBag.Customers = customers;

            return View(qvm);
        }

---

我错过了什么？任何帮助都将不胜感激。

我没有为下面的设置隐藏的值。谢谢，@StephenMuecke

@Html.HiddenFor(model => model.Company)

---

尚未选择公司名称-所选择的只是

CustomerId

（这是您的dropdownlist绑定到的）的值。您没有向我们显示相关代码。并且您的

customer.Company=qvm.CompanyPOST方法中的代码行表示视图模型具有属性
公司
-视图模型不包含数据模型属性。您需要查看哪些代码？视图模型中的所有代码上面已发布的代码。
@Html.HiddenFor(model => model.Company)