c# - 选择对象列表中对象的属性，该对象也在另一个对象列表中

Question

我有下一个架构:

public class Element
{
    public uint Id { get; set; }
    public ICollection<ElementDetails> elementDetails { get; set; }
}
public class ElementDetails
{
    public string ElementTitle { get; set; }
    public string Content { get; set; }
}

还有 List<Element> someList包含数百个元素。我正在尝试获取包含特定文本(我称之为“种子”)的 ElementTitle(字符串)列表。我想要完成的是提前输入。这是我的尝试:

List<Element> suggestedElements = someList.Where(s => s.elementDetails.Any(ss => ss.ElementTitle.Contains(seed))).ToList();
List<string> suggestions = suggestedElements .SelectMany(t => t.elementDetails.Select(x => x.ElementTitle)).ToList() }); // contains all ElementTitle, including those ElementTitle that don't contain the "seed"...

如何去掉那些不包含种子的元素？

Answer 1

List<string> suggestions = someList.SelectMany(x => x.elementDetails)
                                   .Where(y => y.ElementTitle.Contains(seed))
                                   .Select(z => z.ElementTitle)
                                   .ToList();

更简单:

List<string> suggestions  = someList.SelectMany(x => x.elementDetails)
                                    .Select(y => y.ElementTitle);
                                    .Where(z => z.Contains(seed))
                                    .ToList();