Model view controller 试图从Linq查询MVC中填充ViewModel列表“列表不包含…”的定义”错误

我正在尝试构建一个选择题测试应用程序，该应用程序将从控制器向视图传递一系列选择题选择列表。 然后使用foreach循环填充视图，将答案发布回控制器，检查答案并增加每个正确答案的分数，然后更新数据库

我试图使用Linq查询填充视图模型列表以保持控制器精简，我是通过服务层中的一种方法来实现这一点的

模型

Questions (db first)

namespace AccessEsol.Models
{
using System;
using System.Collections.Generic;

public partial class Question
{
    public Question()
    {
        this.ExamDets = new HashSet<ExamDet>();
    }

    public int QuID { get; set; }
    public string Text1 { get; set; }
    public string Text2 { get; set; }
    public string CorrectAnswer { get; set; }
    public string Foil1 { get; set; }
    public string Foil2 { get; set; }
    public string Foil3 { get; set; }
    public string Level_ { get; set; }
    public string GrammarPoint { get; set; }

    public virtual ICollection<ExamDet> ExamDets { get; set; }
}
}

考试

还有一个候选人模型包含以下内容：

以及使用这些模型的视图模型：

namespace AccessEsol.Models
{
public class ExamQuestionsViewModel
{
    public int QuID { get; set; }
    public int CandID { get; set; }
    public int ExamId { get; set;  }
    public string Text1 { get; set; }
    public string Text2 { get; set; }
    public string CorrectAnswer { get; set; }
    public string Foil1 { get; set; }
    public string Foil2 { get; set; }
    public string Foil3 { get; set; }
    public string Level { get; set; }
    public string GrammarPoint { get; set; }

    public virtual ICollection<ExamDet> ExamDets { get; set; }

}
}

这是填充视图模型的方法：

        public static List<ExamQuestionsViewModel> AddQuestions()
    {

        AccessEsolDataEntities db = new AccessEsolDataEntities();

        string questionLevel = GetLevel(); 
        int currentCand = GetCandID();
        int currentExam = GetExamID(); 

        //model = new DataAccess().Populate();
        var qu = (from a in  db.Questions
                 where a.Level_ == questionLevel
                 select a).ToList(); 

    List<ExamQuestionsViewModel> exam = new List<ExamQuestionsViewModel>();


        foreach (var IDs in exam)
        {

            currentCand = exam.CandID;
            currentExam = exam.ExamId;

        }


      return (exam);
    }

我收到的错误消息是

'System.Collections.Generic.List<AccessEsol.Models.ExamQuestionsViewModel>'
does not contain a definition for 'ExamId' and no extension method 
'ExamId' accepting a first argument of type 
'System.Collections.Generic.List<AccessEsol.Models.ExamQuestionsViewModel>'      could be found (are you missing a using directive or an assembly
 reference?

---

我在这里做错了什么？非常感谢所有反馈。

请尝试以下内容，而不是您的foreach：

foreach (var IDs in exam)
{    
    currentCand = IDs.CandID;
    currentExam = IDs.ExamId;    
}

foreach (var IDs in exam)
{    
    currentCand = IDs.CandID;
    currentExam = IDs.ExamId;    
}