I have a list of users and each users have list of hashtags.
In my app I provide a way on searching results by hashtags.
In my api I split the search string to get each hashtags separately and what I try to have is:
The user entity, the number of hashtags in common and the hashtags related.
For example:
My classes are as below:
public class UserDto
{
public List<HashtagDto> Hashtags { get; set; }
}
public class HashtagDto
{
string name { get; set; }
}
public class UserHashtagSearchResultDto
{
public UserDto UserFk { get; set; }
public int CountResults { get; set; }
public List<HashtagDto> HashtagsFk { get; set; }
}
My query:
if (searchText.IsNullOrEmpty())
return null;
var splits = searchText.Split(new string[] { " " }, System.StringSplitOptions.RemoveEmptyEntries);
List<string> hashes = HashtagHelper.ToHashkeys(splits);
if (hashes != null && hashes.Count() > 0)
{
User.GetUsers().Include(h => h.Hashtags).Where(s => hashes.Contains(....).Select((hs) =>
{
return new UserHashtagSearchResultDto
{
}
});
}
Input will be: running swimming
Output will be:
List
Example:
Result1
{
UserFk=User1
CountResults=2 (the two hashtags of this user exists in the hashtag repository)
HashtagsFk=List<Hashtag>{hashtag1, hashtag2}; // (swimming and running}
}
Result1
{
UserFk=User2
CountResults=1 (only the hashtag swimming existsin the hashtag repository)
HashtagsFk=List<Hashtag>{hashtag1}; // (swimming)
}
I don't see how to do it by linq.
Ok this is an answer to my issue.
var userCommon = _userRepository.GetAll().Include(h => h.HashtagUsers).ThenInclude(h => h.HashtagFk)
.Where(s => hashes.Intersect(s.HashtagUsers.Select(h => h.HashtagFk.Code).AsEnumerable()).Count() > 0);
userCommon.ForEach(res =>
{
var result = new HashtagResultSearchDto();
result.UserFk = ObjectMapper.Map<UserDto>(res);
var d = res.HashtagUsers.AsQueryable().Select(h => h.HashtagFk);
result.CountResult = result.Hashtags.Count();
result.UserId = res.Id;
hashtagResultSearchDtos.Add(result);
});
Related
I need to sort my csv file alphabetically and not show the ones that it says "hidden" for (aka. client 4 and client 5) this is the code:
static void Main(string[] args)
{
ReadCSFVFile();
Console.WriteLine();
}
static void ReadCSFVFile()
{
var lines = File.ReadAllLines("Navigation.txt");
var list = new List<Company>();
foreach (var line in lines)
{
var values = line.Split(';' );
var company = new Company() { ID = values[0], MenuName = values[1], ParentID = values[2], IsHidden = values[3], LinkURL = values[4] };
list.Add(company);
}
list.ForEach(x => Console.WriteLine($"{x.ID}\t {x.MenuName}\t {x.ParentID}\t {x.IsHidden}\t {x.LinkURL}"));
}
public class Company
{
public string ID { get; set; }
public string MenuName { get; set; }
public string ParentID { get; set; }
public string IsHidden { get; set; }
public string LinkURL { get; set; }
}
and this is the csv file:
ID;MenuName;ParentID;isHidden;LinkURL
1;Company;NULL;False; /company
2;About Us;1;False; /company/aboutus
3;Mission;1;False; /company/mission
4;Team;2;False; /company/aboutus/team
5;Client 2;10;False; /references/client2
6;Client 1;10;False; /references/client1
7;Client 4;10;True; /references/client4
8;Client 5;10;True; /references/client5
10;References;NULL;False; /references
The below should achieve this for you. I've commented the parts I've added to help out.
list.OrderBy(x => x.MenuName) // Order alphabetically based on MenuName
.Where(x => x.IsHidden != "True") // Filter only for non-hidden items
.ToList().ForEach(
x => Console.WriteLine($"{x.ID}\t {x.MenuName}\t {x.ParentID}\t{x.IsHidden}\t {x.LinkURL}"));
I've tried to find the answer to this but nothing seems to fit it quite right.
Requirement: From a known list of FooObjects, return a list of the Foo Id's whose data satisfies all the search criteria.
Here is my code:
class testClass
{
public class SearchItem
{
string Term { get; set; }
decimal Confidence { get; set; }
}
public class FooObject
{
public Guid Id { get; set; }
public List<Data> Data { get; set; }
}
public class Data
{
public string Text { get; set; }
public decimal Confidence { get; set; }
}
[Test]
public void Test()
{
var searchItems = new List<SearchTerm>
{
new SearchTerm{ Confidence = (decimal)1, Term = "TestWord" },
new SearchTerm{ Confidence = (decimal)1, Term = "TestWord2" },
};
var FooObjects = new List<FooObject>
{
new FooObject{Id = new Guid(), Data = new List<Data>
{
new Data{Text = "TestWord", Confidence = 1},
new Data{Text = "TestWord2", Confidence = 1},
new Data{Text = "SomeOtherWord", Confidence = 1},
}
}
};
//result is a list of the Foo IDs
var result = FooObjects.Where(foo => !searchItems.Select(item => item.Term).Except(foo.Data.Select(dt => dt.Text).Distinct()).Any())
.Select(foo => foo.Id).ToList();
Assert.That(result.Count, Is.EqualTo(1));
searchItems.Add(new SearchTerm{Term = "NotFoundString"});
result = FooObjects.Where(foo => !searchItems.Select(item => item.Term).Except(foo.Data.Select(dt => dt.Text).Distinct()).Any())
.Select(foo => foo.Id).ToList();
Assert.That(result.Count, Is.EqualTo(0));
}
}
I now need to modify this so that I can compare against the confidence of each word
Question:
How do I modify the LINQ to compare the confidence and the Term against my data
Instead of matching any criteria like #dymanoid said in his answer, you should be looking to satisfy all the search items/terms (you are mixing these up in your example code, be consistent).
var result = FooObjects
.Where(f => searchItems.All(
s => f.Data.Exists(d => d.Text == s.Term && d.Confidence == s.Confidence)))
.Select(f => f.Id);
Maybe you're looking for something like this:
var result = FooObjects
.Where(foo => foo.Data.Any(d => searchTerms.Any(
si => d.Term == si.Text && d.Confidence == si.Confidence)))
.Select(foo => foo.Id);
Keep in mind that this search isn't effective - if your data sets are large, the performance will be bad.
What is coming in to the webAPI is this JSON string and becomes deserilized in to this:
List<AddAssignMealView> mealtraiDeserializeObjects = JsonConvert.DeserializeObject<List<AddAssignMealView>>(mealTrainee);
mealtraiDeserializeObjects contains five index's one for each day of the week. Inside that specific index is a class that looks like what is below:
public class AddAssignMealView
{
public int TraineeID { get; set; }
public string DayOfTheWeek { get; set; }
public List<string> MealTypes { get; set; }
public List<int> MealID { get; set; }
public List<string> MealName { get; set; }
}
What I am trying to do is, be able to create a list of MealTrainee(Entity Framework):
public partial class MealTrainee
{
public int MealTraineeID { get; set; } //Ignore this one due to it being a post
public int MealID { get; set; }
public int TraineeID { get; set; }
public string DayOfTheWeek { get; set; }
public string MealType { get; set; }
public string MealName { get; set; }
public virtual Meal Meal { get; set; }
}
So I can be able to use addrange and add the list to the database. I understand how to use zip and combined two list types together if it is a single element. This is different due to it being a list of five elements and each of those five elements containing three lists. If someone could point me in the right direction, that would be helpful.
You can Zip 2 times to combine values from 3 lists into series of tuples. You can use SelectMany to flatten results. For example:
var result = mealtraiDeserializeObjects.SelectMany(c =>
c.MealID.Zip(c.MealName, (id,name) => new {id, name})
.Zip(c.MealTypes, (prev, type) => new {prev.id, prev.name, type})
.Select(r => new MealTrainee
{
TraineeID = c.TraineeID,
DayOfTheWeek = c.DayOfTheWeek,
MealID = r.id,
MealName = r.name,
MealType = r.type,
}));
This is the solution I found. I took it day by day in the sense that the first iteration would be Monday and then the count of meals(Ex:Meal for breakfast, Meal for Lunch) and put them in a count which would be "mealweek". Then I took mealweek and created a new mealtrainee for each count. Then after I made the meal out of the mealtrainee I put it in db.MealTrainees.AddRange and posted all the records.
[ResponseType(typeof(MealTrainee))]
public IHttpActionResult PostMealTrainee([FromBody] string mealTrainee)
{
List<MealTrainee> meals = new List<MealTrainee>();
using (DbContextTransaction dbContextTransaction = db.Database.BeginTransaction())
{
try
{
List<AddAssignMealView> mealtraiDeserializeObjects = JsonConvert.DeserializeObject<List<AddAssignMealView>>(mealTrainee);
foreach (var mealtraiDeserializeObject in mealtraiDeserializeObjects)
{
var mealWeek = mealtraiDeserializeObject.MealID.Select((m, i) => new
{
mealtraiDeserializeObject.TraineeID,
mealtraiDeserializeObject.DayOfTheWeek,
MealID = m,
MealTypes = mealtraiDeserializeObject.MealName[i],
MealName = mealtraiDeserializeObject.MealTypes[i]
}).ToList();
var meal = mealWeek.Select(x => new MealTrainee()
{
DayOfTheWeek = x.DayOfTheWeek,
MealID = x.MealID,
MealName = x.MealName,
MealType = x.MealTypes,
TraineeID = x.TraineeID
}).ToList();
db.MealTrainees.AddRange(meal);
}
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
db.SaveChanges();
dbContextTransaction.Commit();
return Ok(meals);
}
catch (Exception e)
{
dbContextTransaction.Rollback();
Logger.Log(e);
return BadRequest();
}
}
}
I have a List. I need to find the unique ExistingData records by applying Group By. Following code works.
var distinctItemsWorking = myCostPages
.GroupBy(x => new {
x.CostPageContent.Program,
x.CostPageContent.Group,
x.CostPageContent.Sequence })
.Select(y => y.First());
Now I need to convert the unique list into a List. How can we achieve this conversion when we do Grouping?
C# Method
public List<CostPage> GetCostPages(SearchEntity search, int pageIndex, int pageSize)
{
List<ExistingData> AllData = GetExistingData();
var allMatchingValues = from existingDatas in AllData
where existingDatas.CostPageContent.Program == search.Program
select existingDatas;
var query = allMatchingValues;
List<ExistingData> currentSelectionForExistingData = query
.Skip(pageIndex * pageSize)
.Take(pageSize)
.ToList();
//var distinctItems = currentSelectionForExistingData.GroupBy(x => new { x.CostPageContent.Program, x.CostPageContent.Group, x.CostPageContent.Sequence })
// .Select(y => new CostPage()
// {
// CostPageContent = y.CostPageContent
// }
// );
var distinctItemsWorking = currentSelectionForExistingData.GroupBy(x => new { x.CostPageContent.Program, x.CostPageContent.Group, x.CostPageContent.Sequence })
.Select(y => y.First());
List<CostPage> myCostPages = new List<CostPage>();
foreach (ExistingData exist in distinctItemsWorking)
{
CostPage c = new CostPage();
c.CostPageContent = exist.CostPageContent;
myCostPages.Add(c);
}
return myCostPages;
}
Other Classes
public class ExistingData
{
public CostPageNumberContent CostPageContent { get; set; }
public string ItemID { get; set; }
}
public class CostPage
{
public CostPageNumberContent CostPageContent { get; set; }
}
public class CostPageNumberContent
{
public string Program { get; set; }
public string Group { get; set; }
public string Sequence { get; set; }
}
public class SearchEntity
{
public string Program { get; set; }
public string Sequence { get; set; }
public string ItemID { get; set; }
}
If you are trying to replace the foreach, you can do something like this:
var myCostPages = currentSelectionForExistingData
.GroupBy(x => new { x.CostPageContent.Program, x.CostPageContent.Group,
x.CostPageContent.Sequence })
.Select(y => new CostPage { CostPageContent = y.First().CostPageContent })
.ToList();
Putting the creation of the CostPage objects into GroupBy would make no sense. The Select is the correct place to perform this conversion.
I have a collection of strings:
"Alberton;Johannesburg"
"Allendale;Phoenix"
"Brackenhurst;Alberton"
"Cape Town;"
"Durban;"
"Johannesburg;"
"Mayville;Durban"
"Phoenix;Durban"
"Sandton;Johannesburg"
that I want to structure into a hierarchical structure in the fastest possible manner, like:
Johannesburg
Alberton
Brackenhurst
Sandton
Cape Town
Durban
Phoenix
Allandale
Mayville
Currently I have nested for loops and checks, but was hoping I could achieve this with a single LAMBDA query?
The above mentioned strings are in a List.
I prepared lambda-like solution, but you should really think if it's more readable/efficient then your current one:
Helper Extension Method:
public static class ChildrenGroupExtensions
{
public static List<CityInfo> GetChildren(this IEnumerable<IGrouping<string, City>> source, string parentName)
{
var cities = source.SingleOrDefault(g => g.Key == parentName);
if (cities == null)
return new List<CityInfo>();
return cities.Select(c => new CityInfo { Name = c.Name, Children = source.GetChildren(c.Name) }).ToList();
}
}
Helper Classes:
public class City
{
public string Name { get; set; }
public string Parent { get; set; }
}
public class CityInfo
{
public string Name { get; set; }
public List<CityInfo> Children { get; set; }
}
Usage:
var groups = (from i in items
let s = i.Split(new[] { ';' })
select new City { Name = s[0], Parent = s[1] }).GroupBy(e => e.Parent);
var root = groups.GetChildren(string.Empty);
Where items is your List<string>
You can look the results with simple helper method like that one:
private static void PrintTree(List<CityInfo> source, int level)
{
if (source != null)
{
source.ForEach(c =>
{
Enumerable.Range(1, level).ToList().ForEach(i => Console.Write("\t"));
Console.WriteLine(c.Name);
PrintTree(c.Children, level + 1);
});
}
}
And the results are:
Cape Town
Durban
Mayville
Phoenix
Allendale
Johannesburg
Alberton
Brackenhurst
Sandton
You haven't specified any specific data structure so I just used a class called Area with a list of children of itself. Also, it's in 2 lines of linq. There is also no check to see if an area is a child of 2 separate parents as the code is. Here's the code for the test I used(Relevant lines in-between the equals comments):
[TestFixture]
public class CitiesTest
{
[Test]
public void Test()
{
var strings = new List<string>
{
"Alberton;Johannesburg",
"Allendale;Phoenix",
"Brackenhurst;Alberton",
"Cape Town;",
"Durban;",
"Johannesburg;",
"Mayville;Durban",
"Phoenix;Durban",
"Sandton;Johannesburg"
};
//===================================================
var allAreas = strings.SelectMany(x=>x.Split(';')).Where(x=>!string.IsNullOrWhiteSpace(x)).Distinct().ToDictionary(x=>x, x=>new Area{Name = x});
strings.ForEach(area =>
{
var areas = area.Split(';');
if (string.IsNullOrWhiteSpace(areas[1]))
return;
var childArea = allAreas[areas[0]];
if (!allAreas[areas[1]].Children.Contains(childArea))
allAreas[areas[1]].Children.Add(childArea);
childArea.IsParent = false;
});
var result = allAreas.Select(x=>x.Value).Where(x => x.IsParent);
//===================================================
}
public class Area
{
public string Name;
public bool IsParent;
public List<Area> Children { get; set; }
public Area()
{
Children = new List<Area>();
IsParent = true;
}
}
}