c# - 对集合进行排序并根据特定条件对结果进行排名

Question

假设我有以下内容

var searches = new ObservableCollection<Book>();

searches 包含书籍对象

public class Book
{
    public string Title { get; set;}
    public string Desc {get; set;}    
}

我想按匹配的字符串对搜索 进行排序。首先，它会检查 Title，然后根据搜索字符串距 Title 开头的距离对其进行排名。接下来它检查 Desc 并根据搜索字符串与 `Desc.

开头的距离程度对它们进行排名。

例如如果我有

Book 1
Title: ABC Book Title
Desc: The description of book 1

Book 2
Title: Book Title Only
Desc: There's an ABC in the description of book 2

Book 3
Title: Book Title ABC
Desc: ABC is in the beginning

假设搜索关键字是 ABC，我希望对 searches 进行排序，以便获得以下内容。结果将更高的优先级给予标题中包含搜索字符串的项目。

Book 1
Title: ABC Book Title
Desc: The description of book 1

Book 3
Title: Book Title ABC
Desc: ABC is in the beginning

Book 2
Title: Book Title Only
Desc: There's an ABC in the description of book 2

如何使用 LINQ 实现此目的？

Answer 1

您可以使用排名函数为每本书定义一个“分数”，然后按分数排序。

即

var searchString = "ABC";
var results = books.Select(b => new { Book = b, Rank = RankBook(b, searchString) })
                   .OrderBy(r => r.Rank)
                   .Select(r => r.Book.Title);

以及排名函数:

private int RankBook(Book b, string searchString)
{
    int rank = 0;
    if (b.Title.Contains(searchString)) rank += 10;

    if (b.Desc.Contains(searchString)) rank += 5;

    return rank;
}

这就是说:found in title=10 point, found in desc=5 points, so uo get the most relevant books with higher scores.