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Filter List inside List Linq

I have list say list of customers and inside each list there is another list of orders
Class Customer
{
int ID,
string Name
List<Order> orders
}
Class Order{
int ID,
string Name
}
Also have a integer list of filteredorderIds = {1,2,3,4}
I want to filter the list of customers who has got orderIds from filteredorderIds list.
So far I am stuck at query like
var filteredCustomers = Customers.Where(x => x.Orders.Any(filteredorderIds.contains(y => y.Id)));

please give credit to #Johnathan Barclay, since he posted faster than i typed example
void Main()
{
var customers = new List<Customer>(){
new Customer(){
ID =1,
Name = "Cust1",
orders = new List<Order>(){
new Order(){ID = 4, Name = "o11"},
new Order(){ID = 5, Name = "o12"},
new Order(){ID = 6, Name = "o13"}
}
},
new Customer(){
ID = 2,
Name = "Cust2",
orders = new List<Order>(){
new Order(){ID = 3, Name = "o21"},
new Order(){ID = 7, Name = "o22"},
new Order(){ID = 8, Name = "o23"}
}
}
};
customers.Where(w =>
w.orders.Any(w => filteredorderIds.Contains(w.ID))
).Dump();
}
List<int> filteredorderIds = new List<int>() { 1, 2, 3, 4 };
public class Customer
{
public int ID { get; set; }
public string Name { get; set; }
public List<Order> orders { get; set; }
}
public class Order
{
public int ID { get; set; }
public string Name { get; set; }
}

Convert categories into human readable breadcrumbs C#

I need a function that converts categories into flats (see code bellow).
I get categories from the database and then I want to convert them into a breadcrumbs format so I can later display them in a combobox.
using System.Collections.Generic;
namespace ConsoleApp4
{
class Program
{
static void Main(string[] args)
{
var categories = new List<ProductCategory>
{
new ProductCategory { ProductCategoryId = 1, ParentId = null, Name = "Drinks" },
new ProductCategory { ProductCategoryId = 2, ParentId = null, Name = "Food" },
new ProductCategory { ProductCategoryId = 3, ParentId = 1, Name = "Beers" },
new ProductCategory { ProductCategoryId = 4, ParentId = 1, Name = "Wines" },
new ProductCategory { ProductCategoryId = 5, ParentId = 3, Name = "Local beers" },
new ProductCategory { ProductCategoryId = 6, ParentId = 3, Name = "Foreign beers" },
new ProductCategory { ProductCategoryId = 7, ParentId = 4, Name = "Red wines" },
new ProductCategory { ProductCategoryId = 8, ParentId = 4, Name = "White wines" },
};
// todo to get below structure...
var flats = new List<ProductCategoryFlatItem>
{
new ProductCategoryFlatItem { NameWithAncestors = "Drinks", ProductCategoryId = 1 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Beers", ProductCategoryId = 3 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Beers / Local beers", ProductCategoryId = 5 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Beers / Foreingn beers", ProductCategoryId = 6 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Wines", ProductCategoryId = 4 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Wines / Red wines", ProductCategoryId = 7 },
new ProductCategoryFlatItem { NameWithAncestors = "Drinks / Wines / White wines", ProductCategoryId = 8 },
new ProductCategoryFlatItem { NameWithAncestors = "Food", ProductCategoryId = 2 },
};
}
}
public class ProductCategory
{
public int ProductCategoryId { get; set; }
public int? ParentId { get; set; }
public string Name { get; set; }
}
public class ProductCategoryFlatItem
{
public int ProductCategoryId { get; set; }
public string NameWithAncestors { get; set; }
}
}
UPDATE:
I successfully build a tree, and then I am trying to use tree to build breadcrumbs by searching for ancestors, see my code bellow (this is work in progress...)
public interface IProductCategoryExtensions
{
List<ProductCategoryTreeItem> BuildTreeAndGetRoots(List<ProductCategory> allCategories);
List<ProductCategoryFlatItem> CreateComboboxItems(List<ProductCategory> categories);
}
public class ProductCategoryExtensions : IProductCategoryExtensions
{
public List<ProductCategoryTreeItem> BuildTreeAndGetRoots(List<ProductCategory> allCategories)
{
var treeItems = new List<ProductCategoryTreeItem>();
var rootItems = allCategories.Where(x => x.ParentId == null);
foreach (var rootItem in rootItems)
{
treeItems.Add(new ProductCategoryTreeItem
{
Item = rootItem,
Disabled = false,
Parent = null,
Children = GetChildren(allCategories, rootItem)
});
}
return treeItems;
}
private List<ProductCategoryTreeItem> GetChildren(List<ProductCategory> allCategories, ProductCategory productCategory)
{
var children = new List<ProductCategoryTreeItem>();
var childrenTemp = allCategories.Where(x => x.ParentId == productCategory.ProductCategoryId);
foreach (var childTemp in childrenTemp)
{
var child = new ProductCategoryTreeItem
{
Disabled = false,
Item = childTemp,
Children = GetChildren(allCategories, childTemp),
};
children.Add(child);
}
return children;
}
public List<ProductCategoryFlatItem> CreateComboboxItems(List<ProductCategory> categories)
{
var flats = new List<ProductCategoryFlatItem>();
var tree = BuildTreeAndGetRoots(categories);
foreach (var treeItem in tree)
{
flats.Add(CreateFlatItem(treeItem, categories));
if (treeItem.HasChildren)
{
flats.AddRange(GetChildrenFlats(treeItem.Children));
}
}
return flats;
}
private List<ProductCategoryFlatItem> GetChildrenFlats(List<ProductCategoryTreeItem> children)
{
var flatChildren = new List<ProductCategoryFlatItem>();
foreach (var child in children)
{
//if (child.Children != null && child.Children.Count > 0)
// Get
}
return flatChildren;
}
private ProductCategoryFlatItem CreateFlatItem(ProductCategoryTreeItem treeItem, List<ProductCategory> allCategories)
{
var flat = new ProductCategoryFlatItem();
if (treeItem.Parent == null)
{
flat.Description = treeItem.Item.Description;
flat.ProductCategoryId = treeItem.Item.ProductCategoryId;
}
else
{
}
return flat;
}
public List<ProductCategoryTreeItem> BuildTreeAndGetRoots(List<ProductCategory> allCategories)
{
var treeItems = new List<ProductCategoryTreeItem>();
var rootItems = allCategories.Where(x => x.ParentId == null);
foreach (var rootItem in rootItems)
{
treeItems.Add(new ProductCategoryTreeItem
{
Item = rootItem,
Disabled = false,
Parent = null,
Children = GetChildren(allCategories, rootItem)
});
}
return treeItems;
}
}
public class ProductCategoryTreeItem
{
public ProductCategory Item { get; set; }
public bool Disabled { get; set; }
public ProductCategoryTreeItem Parent { get; set; }
public List<ProductCategoryTreeItem> Children { get; set; } = new List<ProductCategoryTreeItem>();
public bool HasChildren
{
get
{
return Children != null && Children.Count > 0;
}
}
}

Sorry this is kinda messy code, but I'll leave the refactoring to you.
Assuming we have two classes:
public class ProductCategory
{
public int ProductCategoryId { get; set; }
public int? ParentId { get; set; }
public string Name { get; set; }
public Dictionary<ProductCategory, int> AncestorsWithHierarchy { get; set; } = new Dictionary<ProductCategory, int>();
}
public class ProductCategoryFlatItem
{
public string NameWithAncestors { get; set; }
public int ProductCategoryId { get; set; }
}
I added AncestorsWithHierarchy to ProductCategory to be able to set up breadcrumb order right.
Then you can do setup a continuous search backwards among ancestors in a recursive way, while adding the hierarchy level to use it for .OrderBy()
var result = new List<ProductCategoryFlatItem>();
Func<ProductCategory, ProductCategory> FindParent = null;
FindParent = thisItem =>
{
var parent = categories.Find(c => c.ProductCategoryId == thisItem.ParentId);
return parent;
};
foreach (var category in categories)
{
int hierarchyLevel = 0;
var parent = FindParent(category);
while (parent != null)
{
category.AncestorsWithHierarchy.Add(parent, hierarchyLevel);
hierarchyLevel++;
parent = FindParent(parent);
}
// Add self since we want it in the breadcrumb
category.AncestorsWithHierarchy.Add(category, -1);
result.Add(new ProductCategoryFlatItem()
{
NameWithAncestors = string.Join(" / ", category.AncestorsWithHierarchy.OrderByDescending(x => x.Value).Select(anc => anc.Key.Name)),
ProductCategoryId = category.ProductCategoryId
});
}
Which gives you your desired result:
However, I would never do this kind of operation during every read. I'm assuming this data will be read much more than it'll be written. So, what I would really do is, to move this logic where you are CRUD'ing to the database and build your breadcrumb there as a new field, and only recalculate if a category changes. This is much better than calculating on every single read request for every single user.

LINQ distinct on groups of information

I have multiple items (List)
I need to get distinct features for the items but the issue is that each item has two features. So both features need to match on GroupTypeId and GroupId to become a distinct group.
I need to group items that have the same features (per above distinct groups found). I don't need features here again at the item level since I will have these per above in a separate object.
I need to keep items order intact, the first item will go in group 1, then second might go in group 1 or group 2 and so on.
Also, each item in group, item number needs to be overwritten per the new sequence in that group.
Can i do above tasks purely with LINQ rather than using nested loops?
In the below sample for items
i have 3 distinct feature groups
and 3 item groups. Item 2 and 4 needs to be grouped together and the line no needs to change to 1 and 2. For item 1 and 3, line number should become as 1.
Need to add to List whose count will be 3
Index[0] will have 2 features and 1 item
Index[1] will have 2 features and 2 items
Index[2] will have 2 features and 1 item
public class ItemPicked
{
public int Id { get; set; }
public string Description { get; set; }
public int LineNumber { get; set; }
public int PartId { get; set; }
public List<ItemFeature> Features { get; set; }
}
public class ItemFeature
{
public string OriginalReceived { get; set; }
public Group Feature { get; set; }
}
public class Group
{
public int Id { get; set; }
public string GroupTypeId { get; set; }
public string GroupId { get; set; }
public int SequenceNo { get; set; }
}
public class PickedGrouping
{
public List<ItemFeature> Features { get; set; }
public List<ItemPicked> Items { get; set; }
}
var SampleFeatures1 = new List<ItemFeature>() {
new ItemFeature {
OriginalReceived = "SomeThing",
Feature = new Group() {
Id = 1, SequenceNo = 1, GroupTypeId = "A", GroupId = "B"
}
},
new ItemFeature {
OriginalReceived = "SomeThing2",
Feature = new Group() {
Id = 2, SequenceNo = 2, GroupTypeId = "Y", GroupId = "Z"
}
}
};
var SampleFeatures2 = new List<ItemFeature>() {
new ItemFeature {
OriginalReceived = "SomeThing3",
Feature = new Group() {
Id = 3, SequenceNo = 3, GroupTypeId = "C", GroupId = "D"
}
},
new ItemFeature {
OriginalReceived = "SomeThing4",
Feature = new Group() {
Id = 4, SequenceNo = 4, GroupTypeId = "X", GroupId = "Y"
}
}
};
var SampleFeatures3 = new List<ItemFeature>() {
new ItemFeature {
OriginalReceived = "SomeThing5",
Feature = new Group() {
Id = 3, SequenceNo = 3, GroupTypeId = "C", GroupId = "D"
}
},
new ItemFeature {
OriginalReceived = "SomeThing5",
Feature = new Group() {
Id = 2, SequenceNo = 2, GroupTypeId = "M", GroupId = "K"
}
}
};
var items = new List<ItemPicked>(){
new ItemPicked{
Id = 1, Description = "Item 1", LineNumber = 1, Features = SampleFeatures1
},
new ItemPicked{
Id = 2, Description = "Item 2", LineNumber = 2, Features = SampleFeatures2
},
new ItemPicked{
Id = 3, Description = "Item 3", LineNumber = 3, Features = SampleFeatures3
},
new ItemPicked{
Id = 4, Description = "Item 4", LineNumber = 4, Features = SampleFeatures2
}
};
var pickedGroupings = new List<PickedGrouping>();
PickedGrouping selectedGroup = null;
foreach (var item in items)
{
var found = 0;
if(item.Features == null || !item.Features.Any())
{
selectedGroup = pickedGroupings.FirstOrDefault(x => x.Features == null || !x.Features.Any());
if (selectedGroup == null) selectedGroup = new PickedGrouping();
selectedGroup.Features.AddRange(item.Features);
}
else
{
foreach (var feature in item.Features)
{
foreach (var pg in pickedGroupings)
{
if ((item.Features == null || !item.Features.Any()) && (pg.Features == null || !pg.Features.Any())){
selectedGroup = pg;
found += 1;
}
else
{
foreach (var pgf in pg.Features)
{
if (pgf.Feature == null) continue;
if (pgf.Feature.GroupId == feature.Feature.GroupId && pgf.Feature.GroupTypeId == feature.Feature.GroupTypeId)
{
selectedGroup = pg;
found += 1;
}
}
}
}
}
if (found < 2)
{
pickedGroupings.Add(new PickedGrouping() { Features = item.Features });
selectedGroup = pickedGroupings[pickedGroupings.Count - 1];
}
}
//add item
if (selectedGroup.Items == null) selectedGroup.Items = new List<ItemPicked>();
selectedGroup.Items.Add(item);
}
//update line number
foreach(var pg in pickedGroupings)
{
var lineNum = 1;
foreach(var item in pg.Items)
{
item.LineNumber = lineNum;
lineNum += 1;
}
}

C# challenge employee tree

I have a c# project, and I've created a class called Employees.
Inside this class, I have a new list:
public class Employees
{
public int Id { get; set; }
public string Name { get; set; }
public int? ManagerId { get; set; }
public List<Employees> employees { get; set; }
}
Imagine that I have the following structure shown in the image:
companytree
Then in the main program, I have this structure to represent the picture above:
class Program
{
static void Main(string[] args)
{
var root = new Employees()
{
Id = 15,
Name = "President",
employees = new List<Employees>()
{
new Employees() {
Id = 23, ManagerId = 15, Name = "Director23",
employees = new List<Employees>()
{
new Employees() {
Id = 21, ManagerId = 23, Name = "Manager21",
employees = new List<Employees>()
{
new Employees() { Id = 31, ManagerId=21, Name = "Employee31" },
new Employees() { Id = 41, ManagerId=21, Name = "Employee41" },
new Employees() { Id = 51, ManagerId=21, Name = "Employee51" }
}
},
new Employees() {
Id = 22, ManagerId = 23, Name = "Manager22",
employees = new List<Employees>()
{
new Employees() { Id = 32, ManagerId=22, Name = "Employee32" },
new Employees() { Id = 42, ManagerId=22, Name = "Employee42" },
new Employees() { Id = 52, ManagerId=22, Name = "Employee52" }
}
}
}
},
new Employees() {
Id = 25, ManagerId = 15, Name = "Director25",
employees = new List<Employees>()
{
new Employees() {
Id = 51, ManagerId = 25, Name = "Manager51",
employees = new List<Employees>()
{
new Employees() { Id = 61, ManagerId=51, Name = "Employee61" },
new Employees() { Id = 71, ManagerId=51, Name = "Employee71" },
new Employees() { Id = 81, ManagerId=51, Name = "Employee81" }
}
},
new Employees() {
Id = 62, ManagerId = 25, Name = "Manager62",
employees = new List<Employees>()
{
new Employees() { Id = 72, ManagerId=62, Name = "Employee72" },
new Employees() { Id = 82, ManagerId=62, Name = "Employee82" }
}
}
}
}
}
};
Console.ReadLine();
}
}
How to create a function where I pass the tree root list of the employee and the ID of any employee of the company and you need to return your manager closer or higher and also the employee itself.
Remembering that you could pass the ID of a director (you would have to return the president), the ID of the manager(you would have to return the director), the ID of the employee (you would have to return the manager), the ID of the presidente return himself.
What better way to do this research taking into account that we can have a much larger hierarchical structure than this example. It would be costly to scan all lists.
Use hastable, dictionary, hashset??

A recursive function is generally used to search a tree. I assumed you fix the variable names as suggested:
public static Employee FindById(Employee root, int id) {
if (root.Id == id)
return root;
else if (root.Employees != null) {
foreach (var e in root.Employees) {
var pe = FindById(e, id);
if (pe != null)
return pe;
}
}
return null;
}
To use, find the employee and then the manager:
var emp = FindById(root, 51);
var manager = emp.ManagerId.HasValue ? FindById(root, emp.ManagerId.Value) : null;

Add there two functions :
public static IDictionary<int, Employees> EmployeesToDictionary(Employees employees)
{
var dictionary = new Dictionary<int, Employees>();
EmployeesToDictionary(employees, dictionary);
return dictionary;
}
private static void EmployeesToDictionary(Employees employees, IDictionary<int, Employees> dictionary)
{
if (employees == null) return;
dictionary.Add(employees.Id, employees);
if (employees.employees == null) return;
foreach (var sub in employees.employees)
{
EmployeesToDictionary(sub);
}
}
And usage :
var id = 5;
var dict = EmployeesToDictionary(root);
var employee = dict[id];
var manager = dict[employee.ManagerId.Value];
Edit :
#haindl Documentation is an admission of failure Yeah you're right.
#devweb I have added the check for the exception. The dictionnary is created only one time, check again

If you want to do a traversal only once, there are this possibility :
public static void FindById(Employees root, int id, out Employees employees, out Employees manager)
{
employees = manager = null;
// todo stack
var stack = new Stack<Employees>();
stack.Push(root);
// all managers seens
var managers = new List<Employees>();
while (stack.Count > 0)
{
var e = stack.Pop();
if (e.Id == id) // if found
{
employees = e;
manager = managers.FirstOrDefault(m => m.Id == e.ManagerId);
return;
}
else if (e.employees != null)
{
// add only managers with employee
managers.Add(e);
foreach (var ep in e.employees)
{
stack.Push(ep);
}
}
}
}

IGrouping trouble

I have the following list
class Programm
{
public static void Main(string[] args)
{
List<Service> Services =new List<Service>
{
new Service
{
Name = "name1",
Prices = new List<BEPrice>
{
new BEPrice
{
Price = 120,
Quantity = 3
}
}
},
new Service
{
Name = "name2",
Prices = new List<BEPrice>
{
new BEPrice
{
Price = 123,
Quantity = 3
}
}
},
new Service
{
Name = "name3",
Prices = new List<BEPrice>
{
new BEPrice
{
Price = 100,
Quantity = 3
}
}
},
new Service
{
Name = "name4",
Prices = new List<BEPrice>
{
new BEPrice
{
Price = 900,
Quantity = 8
}
}
}
};
}
public class Tariff
{
public string Name { get; set; }
public List<BEPrice> Prices { get; set; }
}
public class Service
{
public string Name { get; set; }
public List<BEPrice> Prices { get; set; }
public Tariff Tariff;
}
public class BEPrice
{
public decimal Price { get; set; }
public int Quantity { get; set; }
}
I want a result as
Tariff-1 -> Name - "blabla", Prices = {
Price1 = {Price = 343, Quantity = 3},
Price2 = {Price = 900, Quantity = 8} }
The tariff first price Price1 343 is a sum of 100, 120, 123 for 3 (Quantity) month.
Here is my unsuccessful attemp
foreach (var groupedPrices in Services.Select(s => s.Prices.GroupBy(p => p.Quantity)))
{
foreach (var p in groupedPrices.Select(x => x.Key))
Console.WriteLine(p);
foreach (var price in groupedPrices)
{
_prices.AddRange(price.Select(p => p));
}
}

Not sure what is name blabla, but this is how you can get prices part
var prices = Services
.SelectMany(arg => arg.Prices)
.GroupBy(arg => arg.Quantity)
.Select(arg => new { Price = arg.Sum(x => x.Price), Quantity = arg.Key })
.ToList();