I have two classes one of them is Destinations and the other one is DestinationDetails
public class Destinations
{
public Destinations() { }
public string CarrierName { get; set; }
public List<DestinationDetails> Details { get; set; }
}
public class DestinationDetails
{
public DestinationDetails() { }
public string Destination { get; set; }
public string Type { get; set; }
}
I want to get all string "Destination" in the second class from List of objects from the first class
I have List<Destinations> and I don't want to use for loop or foreach statments
var dest = new Destinations();
//Initialize the details
var destNames = dest.Details.Select(d => d.Destination).ToList();
Are you looking for something like this?
var det = new Destinations();
det.Details = new List<DestinationDetails>();
det.Details.Add(new DestinationDetails() { Destination = "CA" });
det.Details.Add(new DestinationDetails() { Destination = "NJ" });
...
...
var details = new DestinationDetails();
details.Destination = string.Join(",",det.Details.Select(x => x.Destination).ToArray() );
Update:-
provided list of Destinations "allDet", you can get the list of strings as below:-
alldet.Where(x => x.Details != null).SelectMany(x => x.Details.Select(y => y.Destination)).ToList() //With out ToList() it will give you IEnumerable<String>
List<Destinations> AirportDestinations ; // this list has Destinations objects which have Details which have Destination
So by using SelectMany
List<string> cities.AddRange(AirportDestinations.Where(x => x.Details != null).SelectMany(d => d.Details.Select(s => s.Destination)));
Now you have all Destination in all objects in the list
Related
I have a Custom class shown below
internal class RecurringClusterModel
{
public int? From { get; set; }
public int? To { get; set; }
public string REC_Cluster_1 { get; set; }
public string REC_Cluster_2 { get; set; }
public string REC_Cluster_3 { get; set; }
public string REC_Cluster_4 { get; set; }
public string REC_Cluster_5 { get; set; }
public string REC_Cluster_6 { get; set; }
public string REC_Cluster_7 { get; set; }
public string REC_Cluster_8 { get; set; }
public string REC_Cluster_9 { get; set; }
public string REC_Cluster_10 { get; set; }
I have a List of this class
List<RecurringClusterModel> recurringRecords = new List<RecurringClusterModel>();
The data can be in the below format
recurringRecords[0].REC_Cluster_1 = "USA";
recurringRecords[0].REC_Cluster_2 = "UK";
recurringRecords[0].REC_Cluster_3 = "India";
recurringRecords[0].REC_Cluster_4 = "France";
recurringRecords[0].REC_Cluster_5 = "China";
recurringRecords[1].REC_Cluster_1 = "France";
recurringRecords[1].REC_Cluster_2 = "Germany";
recurringRecords[1].REC_Cluster_3 = "Canada";
recurringRecords[1].REC_Cluster_4 = "Russia";
recurringRecords[1].REC_Cluster_5 = "India";
....
I want to find the duplicate records between all the Cluster properties..This is just a subset I have 50 properties till REC_Cluster_50. I want to find out which countries are getting duplicated between the 50 cluster properties of the list.
So in this case India and France are getting duplicated. I can group by individual property and then find out the duplicate by getting the count but then I d have to do it for all the 50 Rec_Clusters property. Not sure if there is a better way of doing it.
Thanks
Since you want to capture the From and To, I suggest you structure your class like this:
internal class RecurringClusterModel
{
public int? From { get; set; }
public int? To { get; set; }
public IEnumerable<string> REC_Clusters { get; set; }
}
Then you can search for duplicates:
var dupes = recs
.Select(r => new
{
r.From,
r.To,
DuplicateClusters = r.REC_Clusters.GroupBy(c => c)
.Where(g => g.Count() > 1) // duplicates
.SelectMany(g => g) // flatten it back
.ToArray() // indexed
})
.Where(r => r.DuplicateClusters.Any()) //only interested in clusters with duplicates
.ToArray();
EDIT
If you want all duplicates, then it will be:
var allDupes = recs.SelectMany(r => r.REC_Clusters)
.Select(r => r.GroupBy(c => c)
.Where(g => g.Count() > 1)
.SelectMany(g => g))
.Where(r => r.Any()).ToArray();
But now you lose track of the From/To
I would add an enumerable to your class that iterates over all properties of that class:
internal class RecurringClusterModel
{
public string REC_Cluster_1 { get; set; }
public string REC_Cluster_2 { get; set; }
public string REC_Cluster_3 { get; set; }
public IEnumerable<string> Clusters => GetAllClusters();
private IEnumerable<string> GetAllClusters()
{
if (!string.IsNullOrEmpty(REC_Cluster_1))
yield return REC_Cluster_1;
if (!string.IsNullOrEmpty(REC_Cluster_2))
yield return REC_Cluster_2;
if (!string.IsNullOrEmpty(REC_Cluster_3))
yield return REC_Cluster_3;
}
}
With this you can flatten the list to the individual clusters and then group by. If you need the original object back again, you have to provide it while flattening. Here is an example:
var clusters = Enumerable
.Range(1, 10)
.Select(_ => new RecurringClusterModel
{
REC_Cluster_1 = _Locations[_Random.Next(_Locations.Count)],
REC_Cluster_2 = _Locations[_Random.Next(_Locations.Count)],
REC_Cluster_3 = _Locations[_Random.Next(_Locations.Count)],
})
.ToList();
var dictionary = clusters
// Flatten the list and preserve original object
.SelectMany(model => model.Clusters.Select(cluster => (cluster, model)))
// Group by flattened value and put original object into each group
.GroupBy(node => node.cluster, node => node.model)
// Take only groups with more than one element (duplicates)
.Where(group => group.Skip(1).Any())
// Depending on further processing you could put the groups into a dictionary.
.ToDictionary(group => group.Key, group => group.ToList());
foreach (var cluster in dictionary)
{
Console.WriteLine(cluster.Key);
foreach (var item in cluster.Value)
{
Console.WriteLine(" " + String.Join(", ", item.Clusters));
}
}
I have a hierarchical result set like so:
Then I have a custom object as such:
public class AuthorizedEntity
{
public Departments Department { get; set; }
public string Username { get; set; }
public List<AuthController> Controllers = new List<AuthController>();
}
public class AuthController
{
public string Name { get; set; }
public List<AuthAction> Actions = new List<AuthAction>();
}
public class AuthAction
{
public string Name { get; set; }
public List<string> Methods = new List<string>();
}
Would it be possible to convert the following data into the respective object? In this particular case, the username is justinfarrugia, Controller = StocktakeController, Actions = Permissions with Methods = Edit Permissions and Set Permissions and Action = StockEvaluation with Method = Update Measurements.
I am looking for the most efficient solution.
I have tried this but it doesn't get me to the desired outcome:
ObjectResult<SP_GetPrivilegesByUsername_Result> lstAuthorizedUsersRaw = dbsp.SP_GetPrivilegesByUsername(inUsername.Trim());
lstAuthorizedUsersRaw.GroupBy(p => p.Cntrollers_Name).ToList().ForEach(r =>
{
authEntity.Controllers.Add(new AuthController()
{
Name = r.Key,
Actions = new List<AuthAction>() {
new AuthAction() {
Name = r.ToList().Select(q => q.HMVAct_Name).FirstOrDefault(),
Methods = r.ToList().Select(w => w.HMVMethd_Name).ToList()
}
}
});
});
Thanks,
You missed second grouping - when you select actions from the controller group:
var lstAuthorizedUsersRaw = dbsp.SP_GetPrivilegesByUsername(inUsername.Trim());
authEntity.Controllers = lstAuthorizedUsersRaw
.GroupBy(p => p.Cntrollers_Name)
.Select(controllerGroup => new AuthController {
Name = controllerGroup.Key,
Actions = controllerGroup
.GroupBy(p => p.HMVAct_Name) // here
.Select(actionGroup => new AuthAction {
Name = actionGroup.Key,
Methods = actionGroup.Select(pu => p.HMVMethd_Name).ToList()
}).ToList()
}).ToList();
I have a question. It's about linq in combination with c#.
I want to create a tree structure from a flatten structure in a pre defined object structure.
The following code which I've got work, but both are not exactly what i want.
In linq:
var result = listAgenderingen.GroupBy(records => records.Agnnummer)
.Select(group => new { AgnNummer = group.Key, Items = group.ToList()}).ToList();
the issue is that this does not result in the object I want.
So I've rewritten this to the following code
List<string> test = listAgenderingen.Select(x => x.Agnnummer).Distinct().ToList();
foreach (var item in test)
{
List<Agendering> listAgendering = listAgenderingen.Where(agend => agend.Agnnummer == item).OrderBy(ord => ord.Agnnummer).ToList();
AgnAgendering AgnAgendering = new AgnAgendering() {AgnNummer =item, Agenderingen = listAgendering };
}
this code actually works correct. but for 200000 records, it's taking a lot of time while the original linq takes a few seconds.
my question is can the linq be rewritten so it will create or convert to the richt object?
the structure of the classes:
public class Agendering
{
public int AgnID { get; set; }
public string Agnnummer { get; set; }
}
public class AgnAgendering
{
public string AgnNummer { get; set; }
public List<Agendering> Agenderingen { get; set; }
}
I hope someone has a sollution.
If I understand correctly, you want:
var result = listAgenderingen.GroupBy(records => records.Agnnummer)
.Select(group => new AgnAgendering { AgnNummer = group.Key, Agenderingen = group.ToList()}).ToList();
Your properties naming makes it absolutely unreadable and unclear.
Assuming that you have a flat structure like:
public class Item
{
public int ID { get; set; }
public int? ParentID { get; set; }
}
and you want a tree-like structure:
public class TreeItem
{
public int ID { get; set; }
public TreeItem Parent { get; set; }
public List<TreeItem> Children { get; set; }
public TreeItem(int id)
{
ID = id;
Children = new List<TreeItem>();
}
public TreeItem(int id, TreeItem parent) : this(id)
{
Parent = parent;
}
}
You can do most optimally in O(n) using Dictionary:
Item[] items = ...;
Dictionary<int, TreeItem> result = new Dictionary<int, TreeItem>();
foreach (var item in items.OrderBy(x => x.ParentID ?? -1))
{
TreeItem current;
if (item.ParentID.HasValue)
{
TreeItem parent = result[item.ParentID]; // guaranteed to exist due to order
current = new TreeItem(item.ID, parent);
parent.Children.Add(current);
} else {
current = new TreeItem(item.ID);
}
}
TreeItem[] treeItems = result.Values.ToArray();
I an having Two Lists. I want to get the matched and unmatched values based on ID and add the results to another List. I can get both of these using Intersect/Except.
But I can get only ID in the resultant variables (matches and unmatches) . I need all the properties in the Template.
List<Template> listForTemplate = new List<Template>();
List<Template1> listForTemplate1 = new List<Template1>();
var matches = listForTemplate .Select(f => f.ID)
.Intersect(listForTemplate1 .Select(b => b.ID));
var ummatches = listForTemplate .Select(f => f.ID)
.Except(listForTemplate1.Select(b => b.ID));
public class Template
{
public string ID{ get; set; }
public string Name{ get; set; }
public string Age{ get; set; }
public string Place{ get; set; }
public string City{ get; set; }
public string State{ get; set; }
public string Country{ get; set; }
}
public class Template1
{
public string ID{ get; set; }
}
If you don't want to implement IEquality for this simple task, you can just modify your LINQ queries:
var matches = listForTemplate.Where(f => listForTemplate1.Any(b => b.ID == f.ID));
and
var unmatches = listForTemplate.Where(f => listForTemplate1.All(b => b.ID != f.ID));
You might want to check for null before accessing ID, but it should work.
You are looking for the overloaded function, with the second parameter IEqualityComparer. So make your comparer ( example: http://www.blackwasp.co.uk/IEqualityComparer.aspx ), and use the same comparer in intersect / except.
And for the generic part: maybe you should have a common interface for templates e.g. ObjectWithID describing that the class have a string ID property. Or simply use dynamic in your comparer (but I think this is very-very antipattern because you can have run time errors if using for the bad type).
You also have a problem: intersecting two collections with two different types will result in a collection of Object (common parent class). Then you have to cast a lot (antipattern). I advise you to make a common abstract class/interface for your template classes, and it is working. If you need to cast the elements back, do not cast, but use the visitior pattern: http://en.wikipedia.org/wiki/Visitor_pattern
Example (good):
static void Main(string[] args)
{
// http://stackoverflow.com/questions/16496998/how-to-copy-a-list-to-another-list-with-comparsion-in-c-sharp
List<Template> listForTemplate = new Template[] {
new Template(){ID = "1"},
new Template(){ID = "2"},
new Template(){ID = "3"},
new Template(){ID = "4"},
new Template(){ID = "5"},
new Template(){ID = "6"},
}.ToList();
List<Template1> listForTemplate1 = new Template1[] {
new Template1(){ID = "1"},
new Template1(){ID = "3"},
new Template1(){ID = "5"}
}.ToList();
var comp = new ObjectWithIDComparer();
var matches = listForTemplate.Intersect(listForTemplate1, comp);
var ummatches = listForTemplate.Except(listForTemplate1, comp);
Console.WriteLine("Matches:");
foreach (var item in matches) // note that item is instance of ObjectWithID
{
Console.WriteLine("{0}", item.ID);
}
Console.WriteLine();
Console.WriteLine("Ummatches:");
foreach (var item in ummatches) // note that item is instance of ObjectWithID
{
Console.WriteLine("{0}", item.ID);
}
Console.WriteLine();
}
}
public class ObjectWithIDComparer : IEqualityComparer<ObjectWithID>
{
public bool Equals(ObjectWithID x, ObjectWithID y)
{
return x.ID == y.ID;
}
public int GetHashCode(ObjectWithID obj)
{
return obj.ID.GetHashCode();
}
}
public interface ObjectWithID {
string ID { get; set; }
}
public class Template : ObjectWithID
{
public string ID { get; set; }
public string Name { get; set; }
public string Age { get; set; }
public string Place { get; set; }
public string City { get; set; }
public string State { get; set; }
public string Country { get; set; }
}
public class Template1 : ObjectWithID
{
public string ID { get; set; }
}
Output:
Matches:
1
3
5
Ummatches:
2
4
6
Press any key to continue . . .
For comparison, this should also work (the first part is a variation on #MAV's answer):
var matches = from item in listForTemplate
join id in listForTemplate1 on item.ID equals id.ID
select item;
var unmatches = listForTemplate.Where(item => matches.All(elem => elem.ID != item.ID));
matches and unmatches will both be IEnumerable<Template> which is the type you require.
However, MAV's answer works fine so I'd go for that one.
As mentioned, Implement the IEqualityComparer<T> interface.
IEqualityComparer<T> MSDN
Then use this as an argument in your method for Except() and Intersect()
Intersect
There is a good example of how to do so on the link for the Intersect() method.
If you don't absolutely have to use LINQ, why not code something like this?
var matches = new List<Template>();
var unmatches = new List<Template>();
foreach (var entry in listForTemplate)
{
bool matched = false;
foreach (var t1Entry in listForTemplate1)
{
if (entry.ID == t1Entry.ID)
{
matches.Add(entry);
matched = true;
break;
}
}
if (!matched)
{
unmatches.Add(entry);
}
}
A disadvantage of the LINQ approach is that you're traversing the lists twice.
I have a problem with Automapper. I set up a test windows form application and below is the code. Also look at the comments after each MessageBox:
public class FirstClass
{
public string FirstProp { get; set; }
public IList<FirstClassChild> Children { get; set; }
}
public class FirstClassChild
{
public string FirstChildProp { get; set; }
}
public class SecondClass
{
public string FirstProp { get; set; }
public string SecondProp { get; set; }
public IList<SecondClassChild> Children { get; set; }
}
public class SecondClassChild
{
public string FirstChildProp { get; set; }
public string SecondChildProp { get; set; }
}
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
AutoMapper.Mapper.CreateMap<FirstClass, SecondClass>();
AutoMapper.Mapper.CreateMap<FirstClassChild, SecondClassChild>();
var f = new FirstClass { FirstProp = "FirstClass" };
f.Children = new List<FirstClassChild> { new FirstClassChild { FirstChildProp = "FirstClass" } };
var s = new SecondClass { FirstProp = "SecondClass", SecondProp = "SecondClass" };
s.Children = new List<SecondClassChild> { new SecondClassChild { FirstChildProp = "SecondClass", SecondChildProp = "SecondClass" } };
AutoMapper.Mapper.Map(f, s);
var fc = new FirstClassChild { FirstChildProp = "FirstClass" };
var sc = new SecondClassChild { FirstChildProp = "SecondClass", SecondChildProp = "SecondClass" };
AutoMapper.Mapper.Map(fc, sc);
MessageBox.Show(sc.FirstChildProp);//FirstClass as expected
MessageBox.Show(sc.SecondChildProp);//SecondClass as expected
MessageBox.Show(s.FirstProp);//FirstClass as expected
MessageBox.Show(s.SecondProp);//SecondClass as expected
MessageBox.Show(s.Children.First().FirstChildProp);//FirstClass as expected
MessageBox.Show(s.Children.First().SecondChildProp);//Empty not expected!!
}
}
What can I do to avoid this? Is this behavior expected?
Anyway can anyone guide me how make SecondClass childs SecondChildProp to remain "SecondClass" as it is before the mapping occurs.
I asked a similar question here and found another similar one here.
I think #PatrickSteele makes a very good point: how is AutoMapper supposed to map a source list to a dest list of existing objects, when the dest list may not necessarily bear any resemblance to the source list? i.e. "But what if one list has 3 and the other list has 5?"
If you are sure that FirstClass and SecondClass have the same number of Children, and if the FirstClass's Nth Child always corresponds to SecondClass's Nth child, you could try something like this:
Mapper.CreateMap<FirstClass, SecondClass>()
.ForMember(m => m.Children, o => o.Ignore())
.AfterMap((src, dest) =>
{
for (var i = 0; i < dest.Children.Count; i++)
Mapper.Map(src.Children[i], dest.Children[i]);
});
or if FirstChildProp is some kind of unique key:
Mapper.CreateMap<FirstClass, SecondClass>()
.ForMember(m => m.Children, o => o.Ignore())
.AfterMap((src, dest) =>
{
foreach (var dChild in dest.Children)
{
var sChild = src.Children.Single(c => c.FirstChildProp == dChild.FirstChildProp);
Mapper.Map(sChild, dChild);
}
});