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Iterate over Entity Framework object properties

I have a table "StaffMembers" that have columns indicating the number of days worked in a month, the properties in the model are as follows:
public class StaffMember
{
public int Id { get; set; }
public string Name { get; set; }
public string Gender { get; set; }
public int Phone { get; set; }
public string Email { get; set; }
public string BirthDate { get; set; }
public int OctDays { get; set; }
public int NovDays { get; set; }
public int DecDays { get; set; }
public int JanDays { get; set; }
public int FebDays { get; set; }
public int MarDays { get; set; }
public int AprDays { get; set; }
}
now I retrieve the specific staffMember using linq:
var staffMember = (from b in db.StaffMembers
where b.Id == Id
select b).FirstOrDefault();
what I want to do is to loop over the months properties in staffMember and add all the worked days together to get total working days in the year.
for example if he worked 10 days in oct and 20 days in dec and 30 days in jan, I want a way to iterate over the months and sum the days.

You can do it by iterating over object properties and apply your condition on it.
static void Main(string[] args)
{
var staffA = new StaffMember();
int totalWorkDays = 0;
staffA.AprDays = 5;
staffA.FebDays = 7;
foreach (var item in staffA.GetType().GetProperties())
{
if (item.Name.EndsWith("Days"))
{
totalWorkDays += (int)item.GetValue(staffA)!;
}
}
Console.WriteLine(totalWorkDays);
}
this snippet prints ( 5 + 7 ) => 12

You can use reflection to iterate over the properties, but I do not recommend this because you have to point anyway which properties you want to take into consideration. That's because you have multiple integer properties like Id and Phone so you cannot indicate in the loop that you want to sum integer properties, you have to show explicitly that you want to sum OctDays etc. or write some algorithms that indicates that the current property is responsible for the month. So the best way (and in my opinion simplier than reflection way) would be just to get each of the month explicit and sum like this:
var sum = staffMember.OctDays + staffMember.NovDays + staffMember.DecDays + staffMember.JanDays + staffMember.FebDays + staffMember.MarDays + staffMember.AprDays

Check if two instances of same class have same data in C#

I'm trying to validate if both my objects have the same values.
here's my class
public class myclass
{
public List<c1> List1{ get; set; }
public List<c2> List2{ get; set; }
public List<c3> List3{ get; set; }
}
public class c1
{
public int Number{ get; set; }
public string Name{ get; set; }
public bool IsAvailable{ get; set; }
}
public class c2
{
public int Id{ get; set; }
public string Text{ get; set; }
public GUID Guid{ get; set; }
}
public class c3
{
public int? Age{ get; set; }
public string Role{ get; set; }
public bool IsDeleted{ get; set; }
}
I have 2 instances of this class and I want to compare the data between both the instances and check if they both are the same or not.
I've tried Serializing both the objects and comparing but that's not working as the items in the list can be in a different order.
I've also tried getting HashSet of individual lists and checking if they are equal.
var s1 = new HashSet<c1>(list1);
var s2= new HashSet<c1>(list2);
return s1.SetEquals(s2);

One solution would be to first order the lists using a standard order, like numeric or alphabetic depending on the types, and then trying something like this
if (myclassInstance1.list1.SequenceEqual(myclassInstance2.list1))
{
//Repeat the cycle 2 more times and then //your code
}
Since this one works comparing the sequence you need to first order the lists and to do that you can maybe use this
EDIT: This is the documentation for the list.sequenceEquals() method

The best way to do this is if you explicitly implement the models with IEqualityComparer in .NET.
using System;
using System.Collections.Generic;
public class Program
{
public class MyClass
{
public List<C1> C1List { get; set; }
public List<C2> C2List { get; set; }
}
public class C1 : IEqualityComparer<C1>
{
public string FirstName { get; set; }
public string LastName { get; set; }
public bool Equals(C1 x, C1 y)
{
if(string.Equals(x.FirstName, y.FirstName, StringComparison.OrdinalIgnoreCase)
&& string.Equals(x.LastName, y.LastName, StringComparison.OrdinalIgnoreCase))
return true;
return false;
}
public int GetHashCode(C1 c)
{
return c.FirstName.Length * c.LastName.Length;
}
}
public class C2 : IEqualityComparer<C2>
{
public string FirstName { get; set; }
public string LastName { get; set; }
public bool Equals(C2 x, C2 y)
{
if(string.Equals(x.FirstName, y.FirstName, StringComparison.OrdinalIgnoreCase)
&& string.Equals(x.LastName, y.LastName, StringComparison.OrdinalIgnoreCase))
return true;
return false;
}
public int GetHashCode(C2 c)
{
return c.FirstName.Length * c.LastName.Length;
}
}
}
The IEqualityComparer will give you full control on "the parameters based on which you call 2 objects equal".
As for the above implementation, I have considered the 2 objects are equal if the FirstName and the LastName are same.

Try to order the list,and then compare the data in it:
List<c1> l1 = list1.OrderBy(c => c.Number).ToList();
List<c1> l2 = list2.OrderBy(c => c.Number).ToList();
bool equalValue = true;
if (l1.Count() == l2.Count()) {
for (int i = 0; i < l1.Count(); i++){
if (l1[i].IsAvailable != l2[i].IsAvailable || l1[i].Number != l2[i].Number || l1[i].Name != l2[i].Name)
{
equalValue = false;
break;
}
}
}
else {
equalValue = false;
}
return equalValue;

Empty string comparison is failing

Currently writing a simple reservation. Right now I have a multidimensional string array that holds the passengers name and I am trying to iterate through that array and see whether there are any open seats so I know whether or not to add them to a waiting list.
// Check how many seats are taken
for (int i = 0; i <= nameArray.GetUpperBound(0); i++)
{
for (int j = 0; j <= nameArray.GetUpperBound(1); j++)
{
if (nameArray[i, j] == "")
{
seatsFilled--;
}
else
{
seatsFilled++;
}
}
}
For some reason when I debug, I notice that this line
if (nameArray[i, j] == "")
Doesn't do anything at all and gets skipped over despite there being no names in the array. I cannot for the life of me figure out why. Any suggestions?

One of the reason i can see is the comparison may have the whitespace. Try this
if(string.IsNullOrWhiteSpace(nameArray[i, j]))

I would do something like this:
First I would create some interfaces and models that would define the structure of the seat. Make sure to account for seat restrictions.
public interface ISeat
{
int RowNumber { get; }
string SeatLetter { get; }
PassangerModel Passenger { get; }
}
We want to allow some of the seats to be restricted based on passenger age and height. Hard coding that into each seat is nasty so instead I created a SeatRestriction class that has a predicate in it. This predicate will take the passenger model in and return a result. So for example you could create a SeatRestriction that checked a passengers height or age to make sure they can open emergency doors.
public class SeatRestriction
{
public Predicate<PassangerModel> Restriction { get; private set; }
public SeatRestriction(Predicate<PassangerModel> restriction)
{
Restriction = restriction;
}
}
The passenger model can actually be much more verbose than this. I'm assuming here no dietary needs. Maybe this is a reservation system for Spirit Airlines.
public class PassangerModel
{
public string Title { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public int Age { get; set; }
public string Gender { get; set; }
public string StreetAddress { get; set; }
public string City { get; set; }
public string State { get; set; }
public string ZipCode { get; set; }
public string CreditCardName { get; set; }
public string CreditCardNumber { get; set; }
public string CreditCardExpiration { get; set; }
public string CreditCardSecurityPin { get; set; }
}
Next We come to our seat class. This class allows us to see if a passenger is assigned to the seat. Take note that it also asserts prior to adding the passenger to the seat if the passenger meets the restrictions, if any.
public interface IRestrictedSeat
{
List<SeatRestriction> Restrictions { get; }
bool AssertQualifiedPassenger(PassangerModel passenger);
}
public class Seat : ISeat, IRestrictedSeat
{
public bool IsSeatReserved { get { return Passenger != null; } }
public int RowNumber { get; private set; }
public string SeatLetter { get; private set; }
public PassangerModel Passenger { get; private set; }
public List<SeatRestriction> Restrictions { get; private set; }
public Seat(int rowNumber, string seatLetter)
{
Restrictions = new List<SeatRestriction>();
RowNumber = rowNumber;
SeatLetter = seatLetter;
}
public bool TryAddPassenger(PassangerModel passanger)
{
if (AssertQualifiedPassenger(passanger))
{
Passenger = passenger;
return true;
}
else
{
return false;
}
}
public bool AssertQualifiedPassenger(PassangerModel passenger)
{
foreach(SeatRestriction restriction in Restrictions)
{
if (!restriction.Restriction(passenger))
{
return false;
}
}
return true;
}
}
Finally we get to the row. Our row knows how manys seats it has and what its number is. You should be able to add seats to it and then call GetAvailableSeats to get the seats that are left in this row.
public class SeatRow
{
public int TotalSeats { get; private set; }
public int RowNumber { get; private set; }
public List<Seat> Seats { get; private set; }
public SeatRow(int seatsInRow, int rowNumber)
{
TotalSeats = seatsInRow;
RowNumber = rowNumber;
}
public bool TryAddSeatToRow(Seat seat)
{
if(Seats.Count <= TotalSeats && seat.RowNumber == RowNumber)
{
Seats.Add(seat);
return true;
}
else
{
return false;
}
}
public IEnumerable<Seat> GetAvailableSeats()
{
return Seats.Where(seat => seat.IsSeatReserved == false);
}
}
The long and short of this answer is there's a million ways to solve CIS problems and to not rely on stack overflow while you're in school/learning. Good luck and welcome to the club :-)

if (nameArray[i, j] == "")
Doesn't do anything at all and gets skipped over despite there being no names in the array.
That line is inside a loop that iterates through the items in the array. If the array is empty then this will never get executed.

FlatBuffers KeyValuePair data type and schema definition

I have an object that I need to send over the network using TCP. I had this working fine, but I have now expanded on my implementation and am having trouble working out how to define my FlatBuffer schema.
The object to be sent is this:
public class Prediction
{
public PredictionMethod PredictionMethod { get; set; }
public NGramPrediction NGramPrediction { get; set; }
public DistancePrediction DistancePrediction { get; set; }
public int NGramOrder { get; set; }
}
PredictionMethod is an enum:
public enum PredictionMethod
{
Distance = 1,
NGram = 2,
}
NGramPrediction looks like this:
public class NGramPrediction
{
public KeyValuePair<char, int> Gram { get; set; }
public double Probability { get; set; }
public string Pattern { get; set; }
private int Total { get; set; }
private int Order { get; set; }
public NGramPrediction(Gram gram)
{
Total = gram.Total();
var orderedKeyPosibilities = gram.Posibilities.OrderByDescending(x => x.Value);
Gram = orderedKeyPosibilities.First();
Pattern = gram.Pattern;
Probability = (double)Gram.Value / Total;
Order = Pattern.Length;
}
}
Gram looks like this:
public class Gram
{
public string Pattern { get; set; }
public Dictionary<char, int> Posibilities { get; set; }
public Gram(List<char> posibilities, int initialValue = 0)
{
Posibilities = new Dictionary<char, int>();
foreach (var posibility in posibilities)
{
Posibilities.Add(posibility, initialValue);
}
}
public int Total()
{
var keys = Posibilities.Keys;
var total = 0;
foreach (var key in keys)
{
var value = Posibilities[key];
total += value;
}
return total;
// return keys.Sum(key => Posibilities[key]);
}
}
DistancePrediction looks like this:
public class DistancePrediction
{
public IIRVector3 Velocity { get; set; }
public float DeltaTime { get; set; }
public IIRVector3 Position { get; set; }
}
and finally, IIRVector3 looks like this:
public class IIRVector3
{
public IIRVector3()
{
X = 0;
Y = 0;
Z = 0;
}
public float X { get; set; }
public float Y { get; set; }
public float Z { get; set; }
}
I'm trying to define my schema for FlatBuffers:
enum FBPredictionMethod
{
Distance = 1,
NGram = 2
}
struct FBIIRVector3
{
X:float;
Y:float;
Z:float;
}
table FBDistancePrediction
{
Velocity:FBIIRVector3;
DeltaTime:float;
Position:FBIIRVector3;
}
table FBGram
{
Pattern:string;
Possibilities: ????
}
table FBNGramPrediction
{
Gram: ????
Probability:float;
Pattern:string;
Total:short;
Order:short;
}
table FBPrediction
{
PredictionMethod:FBPredictionMethod;
NGramPrediction:FBNGramPrediction;
DistancePrediction:FBDistancePrediction;
NGramOrder:short;
}
root_type FlatServerToClientMessage;
I think everything looks correct, but I have no idea what to do for the dictionaries...
FBGram.Possibilities should be a Dictionary<char, int> and FBGram should be KeyValuePair<char, int>.
Note: Gram's constructor takes a List<char> and an int as parameters, while the constructor for NGramPrediction takes a Gram as a parameter.
Could someone help me with my schema, please?

The KeyValuePair should be easy.. either just store them as two seperate fields, or use a struct KeyValuePair { key:byte; value:int; }
The Dictionary could be stored as Possibilities:[KeyValuePair] (using that same struct). If you wanted to save space if Possibilities can be large, then PossibilityKeys:[byte] and PossibilityValues:[int] will be a little bit more compact, but harder to read/write.

how can I swap two child entity values

I have an entity called "Space" and inside it has "Images". Images has an ordering property that is an int. I'm trying to see if there is an easy linq that can be made to swap the ordering values.
public class Space
{
public int SpaceId { get; set; }
public virtual ICollection<SpaceImage> Images { get; set; }
}
public class SpaceImage
{
public int SpaceImageId { get; set; }
public byte[] Image { get; set; }
public byte[] ImageThumbnail { get; set; }
public string ContentType { get; set; }
public int Ordering { get; set; }
}
ex.
an image might have ordering 3 and another will have 6, I want to swap these two numbers for each of these images
public void Swap(int spaceId, int old, int new)
{
//swap 3 and 6 for the ordering value for the two spaceImages that contain these values where spaceId is spaceId
}

In general, LINQ would be used for querying. You could use it to find the appropriate SpaceImage instances, then set the values appropriately:
// Assuming this is a method in the Space class
public void Swap(int oldOrder, int newOrder)
{
var oldInst = this.Images.FirstOrDefault(si => si.Ordering == oldOrder);
var newInst = this.Images.FirstOrDefault(si => si.Ordering == newOrder);
if (oldInst != null && newInst != null)
{
oldInst.Ordering = newOrder;
newInst.Ordering = oldOrder;
}
else
{
// There weren't matching images - handle that case here
}
}