传入字典的模型项是 List 类型，但是这个字典需要一个 IEnumerable 类型的模型项

Question

我在下面遇到一个异常：

传入字典的模型项的类型为“System.Collections.Generic.List1[DropDownList.Models.Department]', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable1[DropDownList.Models.Employee]”。

这是我的模型， Employee.cs：

public class Employee
{
    public int EmployeeId { get; set; }  
    public string EmployeeName { get; set; }
    public int DepartmentId { get; set; }

    public virtual Department Department { get; set; }
}

部门.cs：

public class Department
{
    public int DepartmentId { get; set; }
    public string DeptCode { get; set; }
    public string DepartmentName { get; set;}
    public string Syscode { get; set; }

    public virtual ICollection<Employee> Employees { get; set; }
}

还有我的EmployeesController的索引动作，异常产生的地方：

public ActionResult Index()
{
var employees =
            from dept in db.Departments
            select new
            {
                dept,
                depts = from emp in dept.Employees
                        where dept.Syscode == "isols123"
                        select dept
            };
        var employs = employees
            .AsEnumerable()
           .Select(m => m.dept);
        return View(employs.ToList());
}

这是我的索引视图：

@model IEnumerable<DropDownList.Models.Employee>
.
.
@foreach (var item in Model) {
<tr>
    <td>
        @Html.DisplayFor(modelItem => item.Department.DepartmentName)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.EmployeeName)
    </td>
</tr>
}

出了什么问题，我不知道，我严重卡在这个问题上 :(，任何人都请带我离开这里，在此先感谢..

Answer 1

本质上，代码：

public ActionResult Index()
{
var employees =
            from dept in db.Departments // This makes dept of type Department
            select new
            {
                dept,
                depts = from emp in dept.Employees
                        where dept.Syscode == "isols123"
                        select dept
            };
        var employs = employees
            .AsEnumerable()
           .Select(m => m.dept); // Selects Department
        return View(employs.ToList());
}

返回Departments 的列表（即使变量被称为employs）并且您的视图期望它是Employees 的列表。

这两者都应该匹配才能正常工作。

假设 linq 查询是正确的，这将使它在视图上期望一个部门列表：

@model List<DropDownList.Models.Department>