Question

我目前正在建立一个论坛，允许用户提问并回答问题。为了让用户更容易查找某个问题，我尝试构建搜索引擎。代码：

List<QuestionDto> dto = _db.Questions.Where(x => (x.Title.Contains(temp) || x.Message.Contains(temp) || (x.User.FirstName + " " + x.User.LastName).Contains(temp) || x.User.LastName.Contains(temp)) && (categoryId == null || x.Category.CategoryId == categoryId))
            .Select(question => new QuestionDto { QuestionId = question.QuestionId,
                Votes = question.Votes, Title = question.Title,
                Message = question.Message, CategoryName = question.Category.Name,
                EditDate = question.EditDate, DateOfCreation = question.DateOfCreation,
                User = new UserDto { UserId = question.User.Id, FirstName = question.User.FirstName, LastName = question.User.LastName, ImageFile = question.User.ImageFile },
                Tags = question.Tags.Select(x => x.Tag).ToList()
            }).ToList();

字符串temp用于搜索问题，以查看标题，消息或用户名是否与查询匹配。

我现在想要完成的是根据问题中找到的点击量对结果进行排序。因此，例如，如果用户搜索单词＆＃34; PHP＆＃34;结果将是：

问题1：PHP被发现10次问题2：PHP被发现5次等等。

如何接近这个？

Answer 1

我假设你想要在db with Contains（）中搜索的属性列表中找到临时词的出现位置。

这是一个循序渐进的过程，它将为您提供一个包含问题ID和出现次数的字典。您可以使用此词典订购问题列表。

当然可以优化它。

如果您需要订购问题，可以使用字典并订购。如果您只需要显示出现次数，您将拥有以下列方式为您提供数据的字典：问题#QuestionId，搜索字符串的出现次数。

假设单词是PHP，您将拥有：，等等。记录不会在字典中订购。

我为该词典添加了一个订单步骤。

稍后编辑：如果您尝试在您的方法中使用Regex，请注意您不能在select语句中使用Regex，但是在将所有记录带入内存后（.ToList()之后）可以使用Regex 。请使用以下问题作为参考：Using "Match" in a Linq statement

 List<QuestionDto> dtoQList = _db.Questions.Where(x => (x.Title.Contains(temp) || x.Message.Contains(temp) || (x.User.FirstName + " " + x.User.LastName).Contains(temp) || x.User.LastName.Contains(temp)) && (categoryId == null || x.Category.CategoryId == categoryId))
        .Select(question => new QuestionDto
        {
            QuestionId = question.QuestionId,
            Votes = question.Votes,
            Title = question.Title,
            Message = question.Message,
            CategoryName = question.Category.Name,
            EditDate = question.EditDate,
            DateOfCreation = question.DateOfCreation,
            User = new UserDto { UserId = question.User.Id, FirstName = question.User.FirstName, LastName = question.User.LastName, ImageFile = question.User.ImageFile },
            Tags = question.Tags.Select(x => x.Tag).ToList()
        }).ToList();

        var questionDictionaryMatchings = new Dictionary<int, int>();

        foreach(var question in dtoQList)
        {
            var titleSplited = question.Title.Split(new char[] { '.', '?', '!', ' ', ';', ':', ',' }, StringSplitOptions.RemoveEmptyEntries);

            var messageSplited = question.Message.Split(new char[] { '.', '?', '!', ' ', ';', ':', ',' }, StringSplitOptions.RemoveEmptyEntries);

            var firstNameSplited = question.User.FirstName.Split(new char[] { '.', '?', '!', ' ', ';', ':', ',' }, StringSplitOptions.RemoveEmptyEntries);

            var lastNameSplited = question.User.LastName.Split(new char[] { '.', '?', '!', ' ', ';', ':', ',' }, StringSplitOptions.RemoveEmptyEntries);


            var titleSplitedQuery = from word in titleSplited
                             where word.ToLowerInvariant() == temp.ToLowerInvariant()
                             select word;

            int wordCountTitle = titleSplitedQuery.Count();

            var messageSplitedQuery = from word in messageSplited
                                      where word.ToLowerInvariant() == temp.ToLowerInvariant()
                                    select word;

            int wordCountMessage = messageSplitedQuery.Count();


            var firstNameSplitedQuery = from word in firstNameSplited
                                    where word.ToLowerInvariant() == temp.ToLowerInvariant()
                                    select word;

            int wordCountFirstName = firstNameSplitedQuery.Count();

            var lastNameSplitedQuery = from word in lastNameSplited
                                    where word.ToLowerInvariant() == temp.ToLowerInvariant()
                                    select word;

            int wordCountLastName = lastNameSplitedQuery.Count();

            questionDictionaryMatchings.Add(question.QuestionId, wordCountTitle + wordCountMessage + wordCountFirstName + wordCountLastName);

        }
          //sorted dictionary
          var questionDictionaryMatchingsSorted = from entry in questionDictionaryMatchings orderby entry.Value descending select entry;

根据出现情况对结果进行排序

1 个答案: