c# - 在 C# 中将 foreach 转换为 lambda 表达式

Question

我刚开始使用 lambda 表示法，所以如果我错了，请纠正我的理解。是否可以使用 lambda 在一个语句中为每个循环重写 a？我有以下内容:

模型

public partial class Section
{
    public int SectionID { get; set; }
    public List<Question> questions { get; set; }
    //...
}

public partial class Question
{
    public int QuestionID { get; set; }
    public int SectionID { get; set; }
    //...
}

前缘

List<Section> sections = db.getSections.ToList();
List<Question> questions = db.getQuestions.ToList();

foreach (var section in sections)
{
    List<Question> questionsInSection = new List<Question>();
    foreach (var question in questions)
    {
        if(section.SectionID == question.SectionID)
            questionsInSection.Add(question);
    }
    section.Questions = questionsInSection;
}

Answer 1

List<Section> sections = questions
                        .GroupBy(x=>x.SectionID)
                        .Select(x=>new Section(){SectionID=x.Key,questions=x.ToList()})
                        .ToList()