C# 调用WCF RIA服务会导致空值，即使URI调用有效

我觉得我在使用WCF RIA服务时，一次又一次地遇到了困难

我有一个WCF RIA服务方法，它根据您传递给它的ID参数返回employee。它使用以下方法处理对URI的ajax调用：

/WCF_RIA_ServiceData.svc/GetEmployeeByID?EmployeeID=1

我想在MVC控制器中使用相同的查询，因此我尝试了以下方法：

// GET: /Employee/Details/5
public ActionResult Details(int id)
{
    WCF_RIA_ServiceData y = new WCF_RIA_ServiceData();
    WCF_RIA_ServiceDataService z = new WCF_RIA_ServiceDataService();

    WCF_RIA_Project.Employee employee = (WCF_RIA_Project.Employee)y.GetEmployeeByID(id);
    WCF_RIA_Project.Employee employee2 = (WCF_RIA_Project.Employee)z.GetEmployeeByID(id);

    ViewData["EmployeeID"] = id;
    ViewData["EmployeeFirstName"] = employee.FirstName;
    ViewData["EmployeeLastName"] = employee.LastName;
    return View();
}

以下是WCF RIA服务中的方法：

[Query(HasSideEffects = true)]
    public IQueryable<WCF_RIA_Project.Employee> GetEmployeeByID(int? EmployeeID)
    {
        var empData = from Employee in this.Context.Employees
                      where Employee.Id == EmployeeID
                      select new WCF_RIA_Project.Employee
                      {
                           ID = Employee.Id,
                           FirstName = Employee.FirstName,
                           LastName = Employee.LastName
                      };
        return empData;
    } 

---

我能够解决这个问题，似乎我的主要问题是在错误的名称空间中。默认的是Lightswitch实现，它（我想？）是自动生成的

如果任何人感兴趣，以下是所有工作代码：

控制器方法：

 public ActionResult Details(int id)
    {
        WCF_RIA_Project.WCF_RIA_Service wcfria = new WCF_RIA_Project.WCF_RIA_Service();
        WCF_RIA_Project.Employee employee = wcfria.GetEmployeeByID(id);

        ViewData["EmployeeID"] = id;
        ViewData["EmployeeFirstName"] = employee.FirstName;
        ViewData["EmployeeLastName"] = employee.LastName;
        return View();
    }

WCF RIA服务方法：

[Query(IsComposable=false)]
    public Employee GetEmployeeByID(int? EmployeeID)
    {
        var empData = from Employee in this.Context.Employees
                      where Employee.Id == EmployeeID
                      select new Employee
                      {
                          ID = Employee.Id,
                          FirstName = Employee.FirstName,
                          LastName = Employee.LastName
                      };
        return empData.Single();
    } 

[Query(IsComposable=false)]
    public Employee GetEmployeeByID(int? EmployeeID)
    {
        var empData = from Employee in this.Context.Employees
                      where Employee.Id == EmployeeID
                      select new Employee
                      {
                          ID = Employee.Id,
                          FirstName = Employee.FirstName,
                          LastName = Employee.LastName
                      };
        return empData.Single();
    }