Inside method I have a list that contains grouped data:
var listofData = _context.DBONE.where(x => x.Id==3 && x.Status!=0)
.GroupBy(x => new { x.Name, x.Class })
.Select(q => new { Result = q.ToList() }).ToList();
if (methodParam == 10)
{
data = listofData.Where(x => FunctionCheck(---CANNOT ACCESS THE FIELDS FROM GROUP DATA TO PASS AS PARAMETERS---) == 10).ToList();
}
And this is the function that will receive 2 parameter from the grouped data:
private int FunctionCheck(int id, string name)
{...}
But, I cannot access the desired field inside 'listofData'. I can access only in case the listofData is not using groupBy().
If I understand what you are trying to do correctly, you are able to access your data but you are actually creating a "list of a list"
Watch my example, I think I have reproduced your scenario here:
As you can see, I then have a "result" which contains a list of users where Id == 3. The problem is that you create a new anonymous object with a props that is a list. So if you try the last thing you see in my image above, I think you will be able to access your rows.
The reason is that after your GroupBy call, the result is of a grouping type - every item of your list is an Enumerable of the original item, so you would have to operate on that grouping in a following manner:
// Groups such that all items in that group pass your check
listofData
.Where(group => group.All(item => FunctionCheck(item.Id, item.Name) == 10))
.ToList();
// Groups where at least one item matches
listofData
.Where(group => group.Any(item => FunctionCheck(item.Id, item.Name) == 10))
.ToList();
The desired outcome is not really clear from the question but this is the step you are likely missing.
Another approach which might be potentially useful is pre-filter the colleciton of items before grouping them:
var listOfGroupedDatas = _context.DBONE
.Where(x => x.Id ==3 && x.Status != 0 && FunctionCheck(item.Id, item.Name) == 10)
.GroupBy(x => new { x.Name, x.Class })
.ToList();
// This will result in a list of groupings in which all items pass your check
I think you want to call SelectMany to project into one dimensional array.
var listofData = _context.DBONE.where(x => x.Id==3 && x.Status!=0)
.GroupBy(x => new { x.Name, x.Class })
.SelectMany(q => q.ToList()).ToList();
Related
I need to use equal instead of Contains.
I have an array of codes called selectedDeviceTypeIDs i assume it has two codes {1,2}
I need get result from the query if Devices ids are exactly {1,2} so i have replace selectedDeviceTypeIDs.Contains with selectedDeviceTypeIDs.equal or something like that ...
m => m.Devices.Any(w => selectedDeviceTypeIDs.Contains(w.DeviceTypeID)
if (DeviceTypeIDs != null)
{
Guid[] selectedDeviceTypeIDs = DeviceTypeIDs.Split(',').Select(Guid.Parse).ToArray();
query = query.Where(j => j.HospitalDepartments.Any(jj => jj.Units.Any(m => m.Devices.Any(w => selectedDeviceTypeIDs.Contains(w.DeviceTypeID)))));
}
Use !.Except().Any() to make sure m.Devices doesn't contains any DeviceTypeID not present in selectedDeviceTypeIDs
query = query.Where(j => j.HospitalDepartments.Any(jj => jj.Units
.Where(m => !m.Devices.Select(w => w.DeviceTypeID).Except(selectedDeviceTypeIDs).Any())));
Option 1:
If you care about the Order of the items, use SequenceEqual extension method. This will return false, even if the collection has the items but in different order
m => m.Devices.Any(w => selectedDeviceTypeIDs.SequenceEqual(w.DeviceTypeID)
Option 2:
If you don't care about the order , use All extension method. This will return true, if the items in both collections are same irrespective of the order.
m => m.Devices.Any(w => selectedDeviceTypeIDs.All(w.DeviceTypeID.Contains)
You need to check if the selectedDeviceTypeIDs contains every device, and that every device contains selectedDeviceTypeIDs. You could use this:
query = query
.Where(j =>
j.HospitalDepartments.Any(jj =>
jj.Units.Any(m =>
m.Devices.All(
w => selectedDeviceTypeIDs.Contains(w.DeviceTypeID))
&&
selectedDeviceTypeIDs.All(
g => m.Devices.Select(d => d.DeviceTypeID).Contains(g))
)
)
);
I want to be able to find all orders with items that contain BOTH apples and oranges that I have in a list.
var itemToFind = new List<string>()
{
"apples",
"cookies"
};
How can I rewrite this so that Contains is dynamic?
This returns what I want but how do I make it loop through my list so that it is dynamic?
var query = result
.Where(o => o.OrderItems
.Any(i => i.Item.Name.Contains("apples")))
.Select(x => x)
.Where(y => y.OrderItems
.Any(b => b.Item.Name.Contains("cookies"))).ToList();
// returns 2 orders
Try something like this:
result.Where(o => o.OrderItems.Any(i => itemToFind.All(itf => i.Item.Name.Contains(itf)))).ToList()
This seems to work but not sure if that is the best way.
foreach (var item in listFacets)
{
// append where clause within loop
result = result
.Where(r => r.RecipeFacets
.Any(f => f.Facet.Slug.Contains(item)));
}
I have the a list called orderList of type Order which has two properties. The list looks something like below.
Id Status
123 Good
878 Good
432 Good
123 Void
What I would like to do is to remove any orders that have a Status which is void and any Good orders which have the same Id as a void order. So the result would give me,
Id Status
878 Good
432 Good
What is the best way to do this? Is it just getting a list of void orders using linq and then looping through this new list to remove Good orders which share the same Id?
You can group and filter later, and flatten the groups at the end:
var result= list.GroupBy(e=>e.Id)
.Where(g=>g.Any(r=>r.Status=="Good") && g.All(r=>r.Status!="Void"))
.SelectMany(g=>g);
So you need to group first by your ID, after that specified your data and create new Field Remove which should be true if you have any Status Void in your group status collection. After that take objects only where the Remove is false and in the end create your RootOrder.
var result = list.GroupBy(x => x.ID)
.Select(x => new { ID = x.Key, Status = x.FirstOrDefault().Status, Remove = x.Any(y => y.Status == "Void") })
.Where(g => g.Remove == false)
.Select(r => new RootOrder { ID = r.ID, Status = r.Status }).ToList();
Full code example: dotNetFiddle
One way would be grouping, filtering and flattening the remaining groups - If you want a more 'literal' query you can try the following:
First filter out all of the non-Good Orders using Where:
orderList = orderList.Where(x => x.Status == Status.Good)
Then filter out all of the remaining Orders for which there are non-Good Orders in orderList containing the same Id using Where and Any:
.Where(x => !orderList
.Any(y => y.Status == Status.Void && y.Id == x.Id)
Finally, use the ToList() to take the returned IEnumerable as a List:
orderList = orderList
.Where(x => x.Status == Status.Good)
.Where(x => !orderList
.Any(y => y.Status == Status.Void && y.Id == x.Id)
.ToList();
I have a basic class for an Account (other properties removed for brevity):
public class Account
{
public string Email { get; set; }
}
I have a List<T> of these accounts.
I can remove duplicates based on the e-mail address easily:
var uniques = list.GroupBy(x => x.Email).Select(x => x.First()).ToList();
The list named 'uniques' now contains only one of each account based on e-mail address, any that were duplicates were discarded.
I want to do something a little different and split the list into two.
One list will contain only 'true' unique values, the other list will contain all duplicates.
For example the following list of Account e-mails:
unique#email.com
dupe#email.com
dupe#email.com
Would be split into two lists:
Unique
unique#email.com
Duplicates
dupe#email.com
dupe#email.com
I have been able to achieve this already by creating a list of unique values using the example at the top. I then use .Except() on the original list to get the differences which are the duplicates. Lastly I can loop over each duplicate to 'pop' it out of the unique list and move it to the duplicate list.
Here is a working example on .NET Fiddle
Can I split the list in a more efficient or syntactically sugary way?
I'd be happy to use a third party library if necessary but I'd rather just stick to pure LINQ.
I'm aware of CodeReview but feel the question also fits here.
var groups = list.GroupBy(x => x.Email)
.GroupBy(g => g.Count() == 1 ? 0 : 1)
.OrderBy(g => g.Key)
.Select(g => g.SelectMany(x => x))
.ToList();
groups[0] will be the unique ones and group[1] will be the non-unique ones.
var duplicates = list.GroupBy(x => x) // or x.Property if you are grouping by some property.
.Where(g => g.Count() > 1)
.SelectMany(g => g);
var uniques = list.GroupBy(x => x) // or x.Property if you are grouping by some property.
.Where(g => g.Count() == 1)
.SelectMany(g => g);
Alternatively, once you get one list, you can get the other one using Except:
var uniques = list.Except(duplicates);
// or
var duplicates = list.Except(uniques);
Another way to do it would be to get uniques, and then for duplicates simply get the elements in the original list that aren't in uniques.
IEnumerable<Account> uniques;
IEnumerable<Account> dupes;
dupes = list.Where(d =>
!(uniques = list.GroupBy(x => x.Email)
.Where(g => g.Count() == 1)
.SelectMany(u => u))
.Contains(d));
I have a list of objects that have a string, and int and another int.
I want to be able to create a list of all the objects that have a duplicate string.
Here is what I have so far:
MyObject duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.ToList();
The error I am getting is that I cannot implicitly convert the type System.Collections.Generic.List<string, MyObject> to MyObject
var duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.SelectMany(g=>g)
.ToList();
you need to write
List<MyObject> duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.ToList();
You could use ToLookup to make a nice data structure with all the info you need
var objectsByString = allMyObjects.ToLookup(o => o.MyString);
This will return a Lookup<string, MyObject>. You can get the duplicate strings using:
var duplicateStrings = objectsByString.Where(l => l.Count()>1).Select(l => l.Key);
which will return a IEnumerable<string> with the duplicate strings. And, for each duplicate you can access the actual objects that have duplicates using something like this:
string duplicateKey = duplicateStrings.First();
var duplicateObjects = objectsByString[duplicateKey]
which returns a IEnumerable<MyObject> with the items that have that string.
There are several problem, the first is a List-of-MyObject cannot be assigned to MyObject, so let's use var to ignore this for a second.
var duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.ToList();
Now, the type of duplicates is List<IGrouping<string, MyObject>> (despite the incorrectly reported error message). Whoops, gotta get rid of (or write to code to account for) the groups!
var duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.SelectMany(g => g)
.ToList();
Now the type of duplicates is List<MyObject>, after having selected every ("selected many") object from every group with more than one item. Better, but this still isn't an MyObject. Well, that's fine: fix the declared type of the variable (that var was previously automatically doing)..
List<MyObject> duplicates = /* same as before */;
Or leave var to do it's thing and if an IEnumerable<MyObject> is fine, simply omit the ToList:
var duplicates = allMyObjects.GroupBy(a => a.MyString)
.Where(a => a.Count() > 1)
.SelectMany(g => g);
Go forth and iterate thy duplicates!