This question already has answers here:
LINQ's Distinct() on a particular property
(23 answers)
Closed 8 years ago.
Distinct() is not working. It displays all the repeating values.
I searched for a solution but just got more confused. I tried this :
var categories = db.Orders.OrderBy(c => c.Item1).ToList().Distinct();
var categories = db.Orders.Distinct().OrderBy(c => c.Item1).ToList();
Is there a quick uncomplicated way to make this work?
use GroupBy instead of Distinct
Related
This question already has answers here:
How to get first N elements of a list in C#?
(7 answers)
Closed 4 years ago.
I have a list of objects in which each object has a property called "Frequency" and I want to be able to pick the top 10 objects that have the highest frequencies.
I saw some solutions that are kind of similar to what I am looking to solve using LINQ so any help is appreciated.
You can order the list by descending Frequency and then take the first 10 like this:
var top10 = objectList.OrderByDescending(o => o.Frequency).Take(10);
This question already has answers here:
Like in Lambda Expression and LINQ
(6 answers)
Closed 5 years ago.
I'm trying to filter out results based on an input string, and I need to use SQL LIKE operation for that and not a normal comparison. Couldn't find the solution online(probably didn't use the correct search words) :
return _context.Cities.Where(t => t.Name == cityName);
And I need it to do WHERE t.name LIKE '%CityName%' . How do I simulate it here ?
_context.Cities.Where(t=> t.Name.Contains(cityName));
This question already has answers here:
Distinct in Linq based on only one field of the table
(10 answers)
Closed 7 years ago.
In LINQ if the result that I have is the a list of whole records from the database and I want to do a Distinct on one column of this record, How do I do that?
You could try something as simple as:
var distincts = records.Select(x=>x.ColumnName).Distinct();
This question already has answers here:
Get distinct items from a list
(4 answers)
Linq Distinct() by name for populate a dropdown list with name and value
(7 answers)
LINQ: Distinct values
(8 answers)
Closed 9 years ago.
I have a CarData object with the following properties:
PrimaryKey Make Model Year Drivetrain Country
I have about 1000 of these CarData objects in a List :
List<CarData> CarObjects
Is there a simple way to get a list of the distinct Makes?
var makes = CarObjects.Select(car => car.Make).Distinct();
This transforms the list from a list of CarData to a list of Makes, and then just finds the distinct values of the new list.
You can use Linq:
CarObjects.Select ( c => c.Make ).Distinct().ToList()
var makeList = CarObjects.Select(a => a.Make).Distinct();
Or
List<MakeEnum> = CarObjects.Select(a => a.Make).Distinct().ToList();
As an extra bit of advice, you may want to consider having Make be an enum, since there are (presumably) a finite (and rather small) number of possible makes of cars, instead of piling them into Strings. (You don't make a mention of what kind of property Make is, so maybe you are already doing this).
This question already has an answer here:
Closed 13 years ago.
Possible Duplicate:
Disjoint Union in LINQ
DUPE: Disjoint Union in LINQ
I know this is a simple collection operation,My code is:
var gone = from a in A
where B.Contains(a) == false
select a;
but it not work.
var gone = A.Except(B);