问题描述
我想承认我在 LINQ 方面很弱.我有数据列表.我想按给定值搜索列表拳头,然后按最大出现次数对数据进行排序,即行中的最大时间.
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Cat"}, new SearchResult(){ID=2,Title="dog"}, new SearchResult(){ID=3,Title="Tiger"}, new SearchResult(){ID=4,Title="Cat"}, new SearchResult(){ID=5,Title="cat"}, new SearchResult(){ID=6,Title="dog"}, };
如果我搜索 &使用 "dog cat" 之类的数据对列表进行排序,然后输出将类似于
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=Cat ID=2,Title=dog ID=6,Title=dog
所有 cat 将首先出现,因为这个 cat 关键字在所有行中找到了最大时间,然后 dog 找到了最大时间.
以下数据不会出现,因为它不在搜索词中
ID=3,Title=Tiger
寻找解决方案.谢谢
更新部分代码
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=2,Title="Excavator JCB - ECU P/N: 728/35700"}, new SearchResult(){ID=3,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=4,Title="JCB Excavator - ECU P/N: 728/35700"}, new SearchResult(){ID=5,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=6,Title="dog"}, }; var to_search = new[] { "Geo", "JCB" }; var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); var matched = result.SelectMany(m => m); var completeList = matched.Concat(list.Except(matched)); dataGridView2.DataSource = completeList.ToList();
我尝试在其他应用程序中使用您的逻辑,但它不起作用.根据逻辑,三行首先带有 GEO 关键字,然后接下来的 2 行带有 JCB,然后是无与伦比的其余部分.我需要在你的代码中改变什么.请帮忙.谢谢
推荐答案
这将过滤您的列表并按 Title 对其进行分组,并按组的大小对组进行排序.
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Cat"}, new SearchResult(){ID=2,Title="dog"}, new SearchResult(){ID=3,Title="Tiger"}, new SearchResult(){ID=4,Title="Cat"}, new SearchResult(){ID=5,Title="cat"}, new SearchResult(){ID=6,Title="dog"}, }; var to_search = new[] { "cat", "dog" }; var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); foreach (var group in result) foreach (var element in group) Debug.WriteLine(String.Format("ID={0},Title={1}", element.ID, element.Title));
输出:
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=cat ID=2,Title=dog ID=6,Title=dog
如果您不关心实际的分组,只需使用 SelectMany.
(请注意,此代码将忽略 Title 的大小写.我不知道这是您想要的还是代码中的拼写错误:您使用的是 cat 和 Cat,并且在你的输出只有 Cat,但 dog 没有大写.)
编辑:
要获取不匹配项,可以使用Except:
var unmatched = list.Except(result.SelectMany(m => m)); // beware! contains the tiger!
编辑 2:
var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); var matched = result.SelectMany(m => m); var completeList = matched.Concat(list.Except(matched)); foreach (var element in completeList) Debug.WriteLine(String.Format("ID={0},Title={1}", element.ID, element.Title));
输出
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=cat ID=2,Title=dog ID=6,Title=dog ID=3,Title=Tiger
编辑 3
var result = from searchResult in list let key_string = to_search.FirstOrDefault(ts => searchResult.Title.ToLower().Contains(ts.ToLower())) group searchResult by key_string into Group orderby Group.Count() descending select Group;
问题描述
i like to confess that i am weak in LINQ. i have list with data. i want to search list fist by given value and then sort data by max occurance means which comes maximum time in rows.
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Cat"}, new SearchResult(){ID=2,Title="dog"}, new SearchResult(){ID=3,Title="Tiger"}, new SearchResult(){ID=4,Title="Cat"}, new SearchResult(){ID=5,Title="cat"}, new SearchResult(){ID=6,Title="dog"}, };
if i search & sort list with data like "dog cat" then output will be like
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=Cat ID=2,Title=dog ID=6,Title=dog
all cat will come first because this cat keyword found maximum time in all the rows and then dog found maximum time.
this below data will not come because it is not in search term
ID=3,Title=Tiger
looking for solution. thanks
UPDATE PORTION CODE
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=2,Title="Excavator JCB - ECU P/N: 728/35700"}, new SearchResult(){ID=3,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=4,Title="JCB Excavator - ECU P/N: 728/35700"}, new SearchResult(){ID=5,Title="Geo Prism 1995 - ABS #16213899"}, new SearchResult(){ID=6,Title="dog"}, }; var to_search = new[] { "Geo", "JCB" }; var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); var matched = result.SelectMany(m => m); var completeList = matched.Concat(list.Except(matched)); dataGridView2.DataSource = completeList.ToList();
i try to your logic in another apps but it is not working. according to logic three rows first come with GEO keyword and then next 2 rows comes with JCB and then unmatched rest comes. what i need to change in ur code. please help. thanks
推荐答案
This will filter your list and group it by Title, sorting the groups by their size.
List<SearchResult> list = new List<SearchResult>() { new SearchResult(){ID=1,Title="Cat"}, new SearchResult(){ID=2,Title="dog"}, new SearchResult(){ID=3,Title="Tiger"}, new SearchResult(){ID=4,Title="Cat"}, new SearchResult(){ID=5,Title="cat"}, new SearchResult(){ID=6,Title="dog"}, }; var to_search = new[] { "cat", "dog" }; var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); foreach (var group in result) foreach (var element in group) Debug.WriteLine(String.Format("ID={0},Title={1}", element.ID, element.Title));
Output:
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=cat ID=2,Title=dog ID=6,Title=dog
If you don't care about the actual grouping, just can flatten the list of groups with SelectMany.
(Note that this code will ignore the case of Title. I don't know if this is what you want or if it is a typo in code: you are using cat and Cat, and in your output it is only Cat, but dog is not capitalized.)
Edit:
To get the unmatched items, you can use Except:
var unmatched = list.Except(result.SelectMany(m => m)); // beware! contains the tiger!
Edit 2:
var result = list.Where(sr => to_search.Any(ts => String.Compare(ts, sr.Title, StringComparison.OrdinalIgnoreCase) == 0)) .GroupBy(sr => sr.Title.ToLower()) .OrderByDescending(g => g.Count()); var matched = result.SelectMany(m => m); var completeList = matched.Concat(list.Except(matched)); foreach (var element in completeList) Debug.WriteLine(String.Format("ID={0},Title={1}", element.ID, element.Title));
Output
ID=1,Title=Cat ID=4,Title=Cat ID=5,Title=cat ID=2,Title=dog ID=6,Title=dog ID=3,Title=Tiger
Edit 3
var result = from searchResult in list let key_string = to_search.FirstOrDefault(ts => searchResult.Title.ToLower().Contains(ts.ToLower())) group searchResult by key_string into Group orderby Group.Count() descending select Group;