为什么在这个LINQ语句中忽略了我的Where子句？

Question

提供的Linq声明旨在仅收回有孩子的父母的数据，这些孩子已经读过这本书＆＃34; Huck .........＆＃34;。出于某种原因，我的查询似乎忽略了Where子句，因为我每次都返回整个数据集Parents。这个查询在哪里失败了？为什么Where似乎不会影响结果？

List<Parent> we = Parents.Select(par => new Parent
{
    ParentID = par.ParentID,
    Children = parents.SelectMany(parData => parData.Children).ToList().Where(child => new Child
    {
        ChildID = child.ChildID,
        Books = child.Books
    }.Books.Contains("Huck........")).ToList()
}).ToList();

类

public class Parent
{
    public Parent() { }

    public int ParentID { get { return _parentID; } set { _parentID = value; } }
    public List<Child> Children { get { return _child; } set { _child = value; } }
}
public class Child
{
    private int _childID;
    private List<string> _targets;

    public Child() { }

    public int ChildID { get { return _childID; } set { _childID = value; } }
    public List<string> Books { get { return _books; } set { _books = value; } }
}

表

 Parent ID |     Parent      | Child ID |     Child     |     Books 
1          | John            | 4        | Suzy          | Grapes of...
1          | John            | 4        | Suzy          | Huck........
1          | John            | 5        | James         | The adven...
2          | Sally           | 4        | Suzy          | Grapes of...
2          | Sally           | 4        | Suzy          | Huck........
2          | Sally           | 5        | James         | The adven...
3          | Fred            | 6        | Jane          | Purple......

Answer 1

因此...

.Where(child => new Child
{
    ChildID = child.ChildID,
    Books = child.Books
}.Books.Contains(Convert.ToInt32("Huck........"))

可以缩短为

.Where(child => child.Books.Contains(Convert.ToInt32("Huck........"))

但是，调用Convert.ToInt32("Huck........")并不会向您提供标题为"Huck........"的图书的ID。它会将字符串转换为一个有些无用的数字。