Asp.net mvc 3 无法创建类型为'；MVCAPApplication4.Models.Users'；。仅支持基本类型（'；如Int32、String和Guid'；）

我有一个员工屏幕和一个拥有员工外键的用户实体。如果为任何员工创建了用户，则不应在员工下拉列表中加载该员工。我收到错误“无法创建常量值”

这是我的两个类雇员和用户

    public class EmployeeMaster
    {   
        [Key, System.ComponentModel.DisplayName("Employee ID")]
        public int EmployeeID { get; set; }

        public string Salutation { get; set; }

        [Display(Name = "Last Name")]
        public string LastName { get; set; }

        [Display(Name = "First Name")]
        public string FirstName { get; set; }

        [Display(Name = "Joining Date")]
        public DateTime JoiningDate { get; set; }

        public string FullName
        {
            get { return string.Format("{0} {1} {2}", Salutation, FirstName, LastName); }
        }
    }

    public class Users
    {
        [Required, Key]
        [Display(Name = "User ID")]
        public int UserID { get; set; }

        [Required]
        [StringLength(100, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
        [DataType(DataType.Password)]
        [Display(Name = "Password")]
        public string Password { get; set; }

        [DataType(DataType.Password)]
        [Display(Name = "Confirm password")]
        [Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
        public string ConfirmPassword { get; set; }

        public int EmployeeMasterId
        { get; set; }

        private RHDMSSoftwareDataBase context = new RHDMSSoftwareDataBase();

        //This collection retunrs list of employee for which user is not created.***
        public IEnumerable<EmployeeMaster> SelectedListItem
        {
            get
            {
                var user = context.Users.ToList();
                var employee = (from emp in context.EmployeeMasters
                                from use in user
                                where emp.EmployeeID != use.EmployeeMasterId
                                select emp).AsEnumerable();
                return employee;
            }
        }
    }

这是我的视图代码，在下拉列表中插入值

<div class="editor-label">
            EmployeeMaster
        </div>
        <div class="editor-field">
            @Html.DropDownListFor(model => model.EmployeeMasterId, Model.SelectedListItem.Select(option => new SelectListItem
       {
           Text = (option == null ? "None" : option.FullName),
           Value = option.EmployeeID.ToString(),
           Selected = (Model != null) && (option.EmployeeID == Model.EmployeeMasterId)
       }), "Izaberite"));
            @Html.ValidationMessageFor(model => model.EmployeeMasterId)
        </div>

雇主主管
@Html.DropDownListFor（model=>model.EmployeeMasterId，model.SelectedListItem.Select（option=>newselectListItem
{
Text=（option==null？“无”：option.FullName），
Value=option.EmployeeID.ToString（），
选中=（Model！=null）&&（option.EmployeeID==Model.EmployeeMasterId）
})"依扎贝利特",；
@Html.ValidationMessageFor（model=>model.EmployeeMasterId）

---

我在创建视图时遇到此错误

我试图编辑这个问题，看它是否更清晰，但我不明白创建新EmployeeUser时您想做什么。我建议您澄清您的问题，以便获得一些帮助。您好，我正在尝试筛选用户屏幕上的Employee Master下拉列表，因为我已经创建了一个Employee Master的IEnumarable集合，但当我尝试创建一个新的Employee用户时，它会抛出一个异常“”无法创建ModelApplication4.Models.Users类型的常量值，在此上下文中仅支持基元类型。问题是当您尝试显示下拉列表时？或者下拉列表显示正确，问题是当您即将创建新用户时？问题是当我即将创建新用户时，它在代码行下方显示下拉列表时引发异常：@Html.DropDownListFor（model=>model.EmployeeMasterId，model.SelectedListItem.Select（option=>new SelectListItem）{Text=（option==null？“None”：option.FullName），Value=option.EmployeeID.ToString（），Selected=（Model！=null）&&（option.EmployeeID==Model.EmployeeMasterId）}），“Izaberite”）；在获取EmployeeMasters列表时，请尝试使用context.EmployeeMasters.ToList（），并告诉我。

<div class="editor-label">
            EmployeeMaster
        </div>
        <div class="editor-field">
            @Html.DropDownListFor(model => model.EmployeeMasterId, Model.SelectedListItem.Select(option => new SelectListItem
       {
           Text = (option == null ? "None" : option.FullName),
           Value = option.EmployeeID.ToString(),
           Selected = (Model != null) && (option.EmployeeID == Model.EmployeeMasterId)
       }), "Izaberite"));
            @Html.ValidationMessageFor(model => model.EmployeeMasterId)
        </div>