linq - カスタムタイプとして返​​されるlinq結果セットを取得するにはどうすればよいですか

Question

public class LearnerInfo
{
    public string Id { get; set; }
    public string Name { get; set; }


    public LearnerInfo(string id, string name)
    {
        this.Id = id;
        this.Name = name;
    }
}


public class LearnerCourse
{
    public string Id { get; set; }
    public string ExpiredCount { get; set; }
    public string Soonduecount { get; set; }
    public string Currentmonthcount { get; set; }
    public string Currentmonthplus1count { get; set; }
    public string Currentmonthplus2count { get; set; }
    public string Currentmonthplus3count { get; set; }
    public string Currentmonthplus4count { get; set; }
    public string Currentmonthplus5count { get; set; }
    public string Subtotal { get; set; }


    public LearnerCourse(string id, string exp, string soonDue, string current, string plus1, string plus2,
        string plus3, string plus4, string plus5)
    {
        this.Id = id;
        this.ExpiredCount = exp;
        this.Soonduecount = soonDue;
        this.Currentmonthcount = current;
        this.Currentmonthplus1count = plus1;
        this.Currentmonthplus2count = plus2;
        this.Currentmonthplus3count = plus3;
        this.Currentmonthplus4count = plus4;
        this.Currentmonthplus5count = plus5;
    }


    public LearnerCourse()
    { }
}

public class InfoList : IEnumerable<CombinedInfo>
{

    private List<CombinedInfo> _infoList = new List<CombinedInfo>();

    public InfoList()
    {
        _infoList = new List<CombinedInfo>();
    }


    public void Add(CombinedInfo i)
    {
        _infoList.Add(i);
    }


    public IEnumerator<CombinedInfo> GetEnumerator()
    {
        return _infoList.GetEnumerator();
    }


    //IEnumerable Members
    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        throw new NotImplementedException();
    }
}


public class CombinedInfo
{
    public string Id { get; set; }
    public string ExpiredCount { get; set; }
    public string Soonduecount { get; set; }
    public string Currentmonthcount { get; set; }
    public string Currentmonthplus1count { get; set; }
    public string Currentmonthplus2count { get; set; }
    public string Currentmonthplus3count { get; set; }
    public string Currentmonthplus4count { get; set; }
    public string Currentmonthplus5count { get; set; }
    public string Name { get; set; }
}


    static void Main(string[] args)
    {
        LearnerCourse lc1 = new LearnerCourse("777", "1", "1", "0", "1", "0", "0", "0", "0");
        LearnerCourse lc2 = new LearnerCourse("589", "1", "0", "0", "0", "0", "0", "0", "0");

        LearnerInfo li1 = new LearnerInfo("777", "moe");
        LearnerInfo li2 = new LearnerInfo("589", "larry");

        LearnerCourse[] lCourses = new LearnerCourse[2];
        lCourses[0] = lc1;
        lCourses[1] = lc2;

        LearnerInfo[] linfos = new LearnerInfo[2];
        linfos[0] = li1;
        linfos[1] = li2;


        //test linq join for object array
        var myJoin = (from c in lCourses
                     join i in linfos on c.Id equals i.Id
                    select new {
                         c.ExpiredCount, 
                         c.Soonduecount,
                         c.Currentmonthcount,
                         c.Currentmonthplus1count,
                         c.Currentmonthplus2count,
                         c.Currentmonthplus3count,
                         c.Currentmonthplus4count,
                         c.Currentmonthplus5count,
                         c.Subtotal,
                         i.Id,
                         i.Name
                     });


        foreach (CombinedInfo o in l)
        {
            //loop through and can add to list of type CombinedInfo
        }
}

foreach ループを通過する代わりに、linq クエリから結果セットを取得してリストを返すだけで問題が発生しています。

提案？

Answer 1

2つのこと：

a) 匿名型ではなく、カスタム クラスにプロジェクトします。あなたの場合、すでにCombinedInfo定義しています - それを使用してください。

b)ToList()実行を強制し、結果をList<T>

var list = (from c in lCourses
             join i in linfos on c.Id equals i.Id
            select new  CombinedInfo() {
                 ExpiredCount = c.ExpiredCount, 
                 Soonduecount = c.Soonduecount,
                 Currentmonthcount = c.Currentmonthcount,
                 Currentmonthplus1count = c.Currentmonthplus1count,
                 Currentmonthplus2count = c.Currentmonthplus2count,
                 Currentmonthplus3count = c.Currentmonthplus3count,
                 Currentmonthplus4count = c.Currentmonthplus4count,
                 Currentmonthplus5count = c.Currentmonthplus5count,
                 Subtotal = c.Subtotal,
                 Id  = i.Id,
                 Name = i.Name
             }).ToList();