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C# Counting properties of Class with child/nested objects

I have the following construction of classes, here simplified as child classes of a 'mother' class called DataClass, which also contains one simple method:
public class DataClass
{
public int num { get; set; }
public string code { get; set; }
public PartClass part { get; set; }
public MemberClass member { get; set; }
public int Count()
{
Type t = typeof(DataClass);
return typeof(DataClass).GetProperties().Length;
}
}
public class PartClass
{
public int seriesNum { get; set; }
public string seriesCode { get; set; }
}
public class MemberClass
{
public int versionNum { get; set; }
public SideClass side { get; set; }
}
public class SideClass
{
public string firstDetail { get; set; }
public string secondDetail { get; set; }
public bool include { get; set; }
}
The issue is, I want to refactor the method so that it can give me an accurate counting of all properties found, including the ones in nested or child classes. In the above example, it only counts properties of DataClass, while I wanted it to return 2 for DataClass + 2 for PartClass + 1 for MemberClass + 3 for SideClass, sums up to 8 properties you may set through DataClass.
Can someone help me with this?

You can introduce interface with Count() method
public interface ICountable
{
int Count();
}
And use this interface to mark all types, which properties are participating in Count() calculation.
You can see the generic abstract class to implement this interface below. Generic T parameter is type whose properties need to be calculated. You implement a calculation logic only once and inherit this class where needed. You also go through all of properties, implementing ICountable, to calculate them as well (some kind of recursion)
public abstract class Countable<T> : ICountable
{
public int Count()
{
Type t = typeof(T);
var properties = t.GetProperties();
var countable = properties.Select(p => p.PropertyType).Where(p => typeof(ICountable).IsAssignableFrom(p));
var sum = countable.Sum(c => c.GetProperties().Length);
return properties.Length + sum;
}
}
and inherit it in your classes
public class DataClass : Countable<DataClass>
{
...
}
public class PartClass : Countable<PartClass>
{
...
}
public class MemberClass : Countable<MemberClass>
{
...
}
public class SideClass : Countable<SideClass>
{
...
}
And this is for the test
var dataClass = new DataClass();
var count = dataClass.Count();
It returns 8 as expected

Creating one helper method for different types via interface c#

I have a requirement to order several lists by the same value. But, for whatever reason, these lists contain objects of different types which share this value. Let's call it ChildID.
The simplified model code would look something like this:
public class Child
{
public string ChildID { get; set; }
}
public class Parent
{
public Child Child { get; set; }
}
public class OtherClassID
{
public int ID { get; set; }
public string ChildID { get; set; }
}
public class SomeOtherClass
{
public OtherClassID ID { get; set; }
}
So, in order to avoid code duplication, I tried this:
public interface IHasChildID
{
string GetChildID();
}
public class Child : IHasChildID
{
public string ChildID { get; set; }
public string GetChildID()
{
return ChildID;
}
}
public class Parent : IHasChildID
{
public Child Child { get; set; }
public string GetChildID()
{
return Child.ChildID;
}
}
public class OtherClassID
{
public int ID { get; set; }
public string ChildID { get; set; }
}
public class SomeOtherClass : IHasChildID
{
public OtherClassID ID { get; set; }
public string GetChildID()
{
return ID.ChildID;
}
}
And when I created a helper class with a helper method which takes an interface as a parameter, I expected it to work:
public static class ChildOrderHelper
{
public static IEnumerable<IHasChildID> OrderChildren(IEnumerable<IHasChildID> children)
{
var childrenList = children.ToList();
//do some splitting, ordering and conatenation of lists
return orderedList;
}
}
But, on every helper call I get an error:
List<Child> originalList = GetChildren(); // whatever
// some lines of code
var orderedList = ChildOrderHelper.OrderChildren(originalList).ToList(); // error
Error CS1503 Argument 1: cannot convert from
'System.Collections.Generic.List<NamespaceOne.Child>' to
'System.Collections.Generic.List<NamespaceTwo.IHasChildID>'
And so for every helper call, no matter the type.
One thing to note is that I've given an example with three distinct types that have this value and need to be ordered by it. In the project, there is probably 10 or more.
I guess there is something fundamental I don't yet understand about interface usage, but any help would be appreciated on this matter.

I'm not entirely sure what your overall use case is, but maybe it would be beneficial to make the OrderChildren method generic, as follows:
public static class ChildOrderHelper
{
public static IEnumerable<T> OrderChildren<T>(IEnumerable<T> children) where T : IHasChildID
{
var childrenList = children.ToList();
//just a simple example of what I'm guessing the method could do...
return childrenList.OrderBy(c => c.GetChildID()).ToList();
}
}
And call it as follows:
List<Child> originalList = GetChildren();
List<Child> orderedList = ChildOrderHelper.OrderChildren<Child>(originalList).ToList();

The approach can be taken like defining an interface and then implemenint that one in all the required classes or a base class that can lookup the child id.
Below is a sample of the source code.
using System;
using System.Linq;
using System.Collections.Generic;
using System.Collections;
public class Program
{
public static void Main()
{
var parents = new List<Parent>();
parents.Add(new Parent{ChildId = "123"});
parents.Add(new Parent{ChildId = "321"});
parents.Add(new Parent{ChildId = "456"});
var result = ChildHelpers.OrderChildren(parents);
foreach(var res in result) {
Console.WriteLine(res.ChildId);
}
Console.WriteLine("Hello World");
}
}
public interface IChild {
string ChildId {get;set;}
}
public class Child : IChild {
public string Name {get;set;}
public string ChildId {get;set;}
}
public class Parent : IChild {
public Parent() {
child = new Child();
}
public Child child {get;set;}
public string ChildId {
get{
return child.ChildId;
}
set{
child.ChildId = value;
}
}
}
public class AnotherChild : IChild {
public string Description{get;set;}
public string ChildId {get;set;}
}
public static class ChildHelpers {
public static IEnumerable<IChild> OrderChildren(IEnumerable<IChild> children)
{
return children.OrderBy(c=>c.ChildId).AsEnumerable();
}
}
If you would like to playaround with this sample and see other options if required, please refer this link.

C# - Property return a lenght array

I have three class :
public class Customer
{
public string FirstName { get; set; }
public string LastName { get; set; }
};
public class count
{
public int number
{
get
{
return 1;
}
set
{
}
}
}
public class myclass
{
public Customer[] Customer { get; set; }
public count number { get; set; }
}
And one instance :
myclass myclass = new myclass()
{
Customer = new Customer[]
{
new Customer()
{
FirstName = "FirstName1",
LastName = "LastName1"
},
new Customer()
{
FirstName = "FirstName2",
LastName = "LastName2"
}
},
number = new count()
};
I want the property count.number returns the number of customer in my array Customer[].
I must have a different class to get the number of elements of my array Customer[]
How to do ?
Th

Your property shouldn't have a setter, it should just return the length of the array dynamically. Something like this:
public class myclass
{
public Customer[] Customer { get; set; }
public int number
{
get { return Customer.Length; }
}
}
Then you don't have to manually set it (or, more importantly, manually keep it synchronized as the array changes).
If you must wrap that integer in a class (which you really shouldn't need to, but whatever), then just return an instance of that class:
public class myclass
{
public Customer[] Customer { get; set; }
public count number
{
get { return new count { number = Customer.Length; } }
}
}
However you structure it (that is, whatever reason you have for wrapping primitive values in classes), the point is that you can get the .Length of an array on the fly without having to manually keep track of it yourself. The array knows how long it is.

Passing dynamic type, iterating fields and replacing values

I have 3/4 different models that each contain their own nested model. I need a way of iterating all fields, including those of the nested model and do a string replace (although not all fields are strings).
My initial idea was to write a method which allows for a 'dynamic' type to be passed.
Input model:
Name = Joe
Surname = Smith
Address = new ClientAddress
{
Line1: Item A
Line2: mistake
Line3: mistake
}
My example method:
MyMethod (dynamic passInModel)
{
....
passInModel.Replace("mistake","correction");
return passInModel;
}
Output:
Name = Joe
Surname = Smith
Address = new ClientAddress
{
Line1: Item A
Line2: correction
Line3: correction
}
Despite trying various ways of doing it I've not had any success in writing something that does the job.

You could write a method that accepts an object and use reflection to iterate through all the fields, but you're getting into messy territory there. In my opinion, even using dynamic here is messy.
Consider using a modified visitor pattern here. If your domain objects look like this:
public class ModelBase
{
}
public class MyModel1 : ModelBase
{
public string Name { get; set; }
public string Surname { get; set; }
public ClientAddress Address { get; set; }
}
public class MyModel2 : ModelBase
{
public string CompanyName { get; set; }
public string Region { get; set; }
public CompanyAddress Address { get; set; }
}
public class ClientAddress
{
public string Line1 { get; set; }
public string Line2 { get; set; }
public string Line3 { get; set; }
}
public class CompanyAddress
{
public string Line1 { get; set; }
public string Line2 { get; set; }
public List<string> AdditionalLines { get; set; }
}
Write a visitor that takes an abstract ModelBase and dispatches the correct type-safe visitor:
public class ModelFixVisitor
{
public ModelBase Visit(ModelBase model)
{
var asModel1 = model as MyModel1;
if (asModel1 != null)
{
return new Model1FixVisitor().Visit(asModel1);
}
var asModel2 = model as MyModel2;
if (asModel2 != null)
{
return new Model2FixVisitor().Visit(asModel2);
}
throw new NotImplementedException("Unknown model type.");
}
}
Then write a simple class for each type (and subtype) you need to visit:
public class Model1FixVisitor
{
public MyModel1 Visit(MyModel1 model)
{
model.Name = new StringFixVisitor().Visit(model.Name);
model.Surname = new StringFixVisitor().Visit(model.Surname);
model.Address = new ClientAddressFixVisitor().Visit(model.Address);
return model;
}
}
public class Model2FixVisitor
{
public MyModel2 Visit(MyModel2 model)
{
model.CompanyName = new StringFixVisitor().Visit(model.CompanyName);
model.Region = new StringFixVisitor().Visit(model.Region);
model.Address = new CompanyAddressFixVisitor().Visit(model.Address);
return model;
}
}
public class ClientAddressFixVisitor
{
public ClientAddress Visit(ClientAddress address)
{
address.Line1 = new StringFixVisitor().Visit(address.Line1);
address.Line2 = new StringFixVisitor().Visit(address.Line2);
address.Line3 = new StringFixVisitor().Visit(address.Line3);
return address;
}
}
public class CompanyAddressFixVisitor
{
public CompanyAddress Visit(CompanyAddress address)
{
address.Line1 = new StringFixVisitor().Visit(address.Line1);
address.Line2 = new StringFixVisitor().Visit(address.Line2);
address.AdditionalLines = new StringListFixVisitor().Visit(address.AdditionalLines);
return address;
}
}
public class StringFixVisitor
{
public string Visit(string element)
{
return element.Replace("mistake", "correction");
}
}
public class StringListFixVisitor
{
public List<string> Visit(List<string> elements)
{
return elements
.Select(x => new StringFixVisitor().Visit(x))
.ToList();
}
}
I'm sure the code could be refactored and optimized, but it should express the general idea.
What I like about this type of solution is that it breaks the problem down into small, manageable chunks: How do I fix a string? How do I fix a ClientAddress?
Fixing entire models then becomes simple composition of these smaller classes. It's a little more verbose, but you get to keep type safety, and don't have to mess with reflection.

You can use the power of .Net reflection to solve this.
I created a class called DeepStringReplacer. Using reflection it iterates through object properties and if the type is string, perform string replace.
Check the code below:
public class DeepStringReplacer
{
public object Replace(object input, string oldValue, string newValue)
{
if (input is string)
{
return input.ToString().Replace(oldValue, newValue);
}
var fields = input.GetType().GetProperties();
foreach (var field in fields)
{
var fieldValue = field.GetValue(input);
field.SetValue(input, Replace(fieldValue, oldValue, newValue));
}
return input;
}
}
public class Person
{
public string Name { get; set; }
public string Surname { get; set; }
public ClientAddress Address { get; set; }
}
public class ClientAddress
{
public string Line1 { get; set; }
public string Line2 { get; set; }
public string Line3 { get; set; }
}

How to make two similar functions into one function?

I have two functions that do the basically same thing on two different classes.... each class has different properties.
For example:
public class ClassA
{
public int ColorID {get;set;}
public string ColorDescription {get;set;}
}
public class ClassB
{
public int TypeID {get;set;}
public string TypeDescription {get;set;}
}
public void ExFunctionSaveA(ClassA aClass)
{
aClass.ColorID=1;
aClass.ColorDescription="My Color";
Save();
}
public void ExFunctionSaveB(ClassB bClass)
{
bClass.TypeID=2;
bClass.TypeDescription="My Type";
Save();
}
As you can see the classes and the functions have the same type structure, just the property names are different... but I feel like I am repeating code doing this
Is there a way to make ExFunctionA and ExFunctionB into one function, so that I could use this for all classes that have similar structure
I know I could do some sort of generic thing like
public void ExFunctionSave<T>() // T is either ClassA or ClassB
{
.
.
.
.
Save();
}
but how would I handle the properties of each

Rather than using a generic, why not use inheritance to solve this?
public class theBase
{
string ID;
string Description;
}
public class theColor : theBase
{
}
public class theType : theBase
{
}
public void ExFunctionSaveA(theBase base)
{
base.ID=1;
base.Description="My Color";
Save();
}

If you can alter the definitions of your classes, then the best approach would be to make them implement a common interface that contains the properties you want to access:
public interface IDescribable
{
int ID { get; set; }
string Description { get; set; }
}
public class ClassA
{
public int ID { get; set; }
public string Description { get; set; }
public int ColorID
{
get { return ID; }
set { ID = value; }
}
public string ColorDescription
{
get { return Description; }
set { Description = value; }
}
}
public class ClassB
{
public int ID { get; set; }
public string Description { get; set; }
public int TypeID
{
get { return ID; }
set { ID = value; }
}
public string TypeDescription
{
get { return Description; }
set { Description = value; }
}
}
public void ExFunctionSave(IDescribable d, int id, string desc)
{
d.ID = id;
d.Description = desc;
Save();
}

Nothing more you can do unless the the 2 classes implement the same interface which has the function. In your case, even the function signatures are different.

You could define an Interface with attributes id and description.
The clases that has this structure could implement that interface.
And your method receive as parameter the interface and execute the moethods ...

Take a look at Reflection.
Reflection will let your code receive a ClassA, and discover that it has a ColourID and a ColorDescription. Likewise, when you receive a ClassB, you can discover its TypeID and TypeDescription. It's cool.
I would probably recommend a common interface, at least for your example, but if you're trying to something more complex and more generic, Reflection is the way to go.