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Compare properties in request if they have equal value C#

I want to compare if the properties in the request have the same value. I have the following json that I use for request via PostMan.
“request”:[ {
“Id”: “1234567”,
“Position”: “1”,
“IsSet”: true
},
{
“Id”: “1234587”,
“Position”: “1”,
“IsSet”: true
},
]
In the code I want to compare if properties Position and IsSet has the same value foreach id in the request. If they don’t to throw error.
public class Info
{
public string Id {get; set;}
public string Position {get; set;}
public bool IsSet {get; set;}
}
I have method called Validate to validate those properties.
public class Validate(Info context)
{
foreach (var item in context)
{
// what code should check this
}
}

You could use LINQs Select and Distinct for that purpose.
Here's a sample "Validate" method.
List<Test> objs = new List<Test>()
{
new Test(){ Position = "random position 1", IsSet = true, Id = 123 },
new Test(){ Position = "random position 2", IsSet = true, Id = 123 },
new Test(){ Position = "random position 3", IsSet = true, Id = 123 }
};
if(objs.Count() > 1){
var query = objs.Select(p => new { p.Id, p.IsSet }).Distinct();
var allTheSame = query.Count() == 1;
Console.WriteLine(allTheSame);
}else{
Console.WriteLine("Nothing To Compare Against");
}
}
The logic here is to check if there's more than 1 item in the list - just so we know there's something to compare the values against.
If more than one, select the properties you want to match objects on and call distinct on it.
Then we get the count of the distinct values, if they all match we will always get 1 returned from the query.Count() hence the boolean check.
At this point if allTheSame is false you can throw your error instead of the Console.WriteLine
In the second Console.WriteLine you can always return true since there's nothing to compare making it distinct enough.
Here's a sample dotNetFiddle.

I like Adriani6's answer. But it works only with simple classes. Best solution i think is Equals method. You can easy generate it with Resharper (Alt+insert, Equaliti members):
public class Info
{
protected bool Equals(Info other)
{
return string.Equals(Id, other.Id) && string.Equals(Position, other.Position) && IsSet == other.IsSet;
}
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj)) return false;
if (ReferenceEquals(this, obj)) return true;
if (obj.GetType() != this.GetType()) return false;
return Equals((Info) obj);
}
public override int GetHashCode()
{
unchecked
{
var hashCode = (Id != null ? Id.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ (Position != null ? Position.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ IsSet.GetHashCode();
return hashCode;
}
}
public string Id { get; set; }
public string Position { get; set; }
public bool IsSet { get; set; }
}

You could simply step through your list in your Validation method with a nested loop.
Assuming it's an IEnumerable like an array or List you could do the following:
// not a class, context is IEnumerable, not a single entitry
// Returns true if OK, false if any element is not the same.
// 'Sameness' (equality) defined in Info-class as implemented by IEquatable
public bool Validate(IEnumerable<Info> context)
{
for (int i = 0; i < context.Count(); i++)
{
for (int j = i + 1; j < context.Count(); j++)
{
if (!context[i].Equals(context[j])) {return false;}
}
}
return true;
}
And Info with IEquatable
public class Info : IEquatable<Info>
{
protected bool Equals(Info other)
{
return string.Equals(Id, other.Id) && string.Equals(Position, other.Position) && IsSet == other.IsSet;
}
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj)) return false;
if (ReferenceEquals(this, obj)) return true;
if (obj.GetType() != this.GetType()) return false;
return Equals((Info) obj);
}
public override int GetHashCode()
{
unchecked
{
var hashCode = (Id != null ? Id.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ (Position != null ? Position.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ IsSet.GetHashCode();
return hashCode;
}
}
public string Id { get; set; }
public string Position { get; set; }
public bool IsSet { get; set; }
}
If you want to be fancy you can overload == and != operators like so:
public static bool operator ==(Info lhs, Info rhs) { return lhs.Equals(rhs); }
public static bool operator !=(Info lhs, Info rhs) { return !(lhs == rhs); }

How to find not matching records in Generic List in C# [duplicate]

This question already has answers here:
Using Linq Except not Working as I Thought
(5 answers)
Closed 4 years ago.
I have two Generic List object, I want to get records which are not matching in second Generic list object. Below is my code. But it returning all records.
I want to ignore matching record in first list.
public class CuratedIncludeUid
{
public string type { get; set; }
public string uid { get; set; }
}
List<CuratedIncludeUid> newUids = new List<CuratedIncludeUid>();
newUids.Add(new CuratedIncludeUid { type = "series", uid = "600" });
List<CuratedIncludeUid> liExistingUids = new List<CuratedIncludeUid>();
liExistingUids.Add(new CuratedIncludeUid { type = "series", uid = "600" });
liExistingUids.Add(new CuratedIncludeUid { type = "series", uid = "200" });
var ied = liExistingUids.Except(newUids).ToList(); ;
foreach (var row in ied)
{
Console.WriteLine("Uid:" + row.uid + "type:" + row.type);
}
Console.Read();
I am getting Output as below
Uid:600type:series
Uid:200type:series
**My expected output as below
Uid:200type:series**

Either override Equals and GetHashCode
public class CuratedIncludeUid
{
public string type { get; set; }
public string uid { get; set; }
protected bool Equals(CuratedIncludeUid other)
{
return string.Equals(type, other.type) && string.Equals(uid, other.uid);
}
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj)) return false;
if (ReferenceEquals(this, obj)) return true;
return Equals((CuratedIncludeUid) obj);
}
public override int GetHashCode()
{
unchecked
{
return ((type != null ? type.GetHashCode() : 0) * 397) ^ (uid != null ? uid.GetHashCode() : 0);
}
}
}
Or passing an IEqualityComparer to Except
public class CuratedIncludeUidEqualityComparer : IEqualityComparer<CuratedIncludeUid>
{
public bool Equals(CuratedIncludeUid x, CuratedIncludeUid y)
{
if (ReferenceEquals(x, y)) return true;
if (ReferenceEquals(x, null) || ReferenceEquals(y, null)) return false;
return string.Equals(x.type, y.type) && string.Equals(x.uid, y.uid);
}
public int GetHashCode(CuratedIncludeUid obj)
{
unchecked
{
return ((obj.type != null ? obj.type.GetHashCode() : 0) * 397) ^ (obj.uid != null ? obj.uid.GetHashCode() : 0);
}
}
}
var ied = liExistingUids.Except(newUids, new CuratedIncludeUidEqualityComparer()).ToList();

Either, you can implement Equals and GetHashCode or IEqualityComparer, or you can also do the following:
With All:
var ied = liExistingUids.Except(newUids).ToList();
liExistingUids
.Where(x => newUids.All(y => y.type != x.type && y.series != x.series))
.ToList();
With Any:
liExistingUids
.Where(x => !newUids.Any(y => y.type == x.type && y.series == x.series))
.ToList();

Trying to set up a CompareLists method with an overridden Equals/Gethash code methods

I'm trying to set up a way to compare some nested lists with objects that I'm importing from MongoDB. I have already set up the lists object:
public class SecurityGroup
{
public ObjectId Id { get; set; }
public string GroupID { get; set; }
public string GroupName{ get; set; }
public List<IpPermission> IpPermissions { get; set; }
public override string ToString()
{
return string.Format("groupid : {0}, groupname : {1} ", GroupID, GroupName );
}
With in that class I also have an overridden Equals method in place.
public override bool Equals(object obj)
{
SecurityGroup secGroup = obj as SecurityGroup;
if (secGroup == null)
{
return false;
}
if (!string.Equals(GroupID, secGroup.GroupID, StringComparison.OrdinalIgnoreCase))
{
return false;
}
if (!string.Equals(GroupName,secGroup.GroupName, StringComparison.OrdinalIgnoreCase))
{
return false;
}
I'm not sure if I need to post the class used for the nested loop but there's an IEquatable interface and the entireity of this class is EXACTLY like the SecurityGroup class I just posted.
//Compare IpPermissions
var diff1 = IpPermissions.Except(secGroup.IpPermissions);
var diff2 = secGroup.IpPermissions.Except(IpPermissions);
if (diff1.Any() || diff2.Any())
{
return false;
}
return true;
}
Now here's the Hashcode method that I set up:
public override int GetHashCode()
{
unchecked
{
const int HashingBase = (int)2166136261;
const int HashingMultiplier = 16777619;
int hash = HashingBase;
hash = (hash * HashingMultiplier) ^ (!Object.ReferenceEquals(null, IpPort) ? IpPort.GetHashCode() : 0);
hash = (hash * HashingMultiplier) ^ (!Object.ReferenceEquals(null, IpProtocol) ? IpProtocol.GetHashCode() : 0);
hash = (hash * HashingMultiplier) ^ (!Object.ReferenceEquals(null, IpRanges) ? IpRanges.GetHashCode() : 0);
return hash;
}
}
}
}
That essentially conludes the code I have in place to set up the framework for my comparesList method. Now here's where I'm having issues. I'm trying to set up the compare lists method and it's just giving me underscored red lines on the 'public static' part. The thing I can't figure out is the error it's giving me for the 'foreach' statements. It's saying, "Cannot convert element type 'AwsInstanceProfile1.Entity.SecurityGroup' to iterator type 'Amazon.EC2.Model.SecurityGroup'" Which is really weird because I should in theory have the framework set up to allow the lists into these objects. Here's the rest of the method:
public static bool CompareLists(List<Entity.SecurityGroup> list1, List<Entity.SecurityGroup> list2) =>
{
if (list1 == null || list2 == null)
return list1 == list2;
Dictionary<SecurityGroup, int> hash = new Dictionary<SecurityGroup, int>();
foreach (SecurityGroup secGroup in list1)
{
if (hash.ContainsKey(secGroup))
{
hash[secGroup]++;
}
else
{
hash.Add(secGroup, 1);
}
}
foreach (SecurityGroup secGroup in list2)
{
if (!hash.ContainsKey(secGroup) || hash[secGroup] == 0)
{
return false;
}
hash[secGroup]--;
}
return true;
}

How to compare two lists of objects?

I have a simple class in C#:
public class Customer
{
public string CustomerName { get; set; }
public int CustomerId { get; set; }
public int RegionId { get; set; }
}
The Customers are stored in a List CustomersA and additionally i have a second with List CustomersB. CustomersB is the "Truth".
I need to find out
customers in CustomersB but not in CustomersA (by CustomerID)
customers in CustomersA but not in CustomersB (by CustomerID) (the same as above)
customers in CustomersB also with the same CustomerID in CustomerA but different CustomerName
How could i achieve this with C#?

You should use LINQ for set operations on data:
•customers in CustomersB but not in CustomersA (by CustomerID)
var query = customersB.Where(cB => !customersA.Any(cA => cA.Id == cB.Id)).ToList();
•customers in CustomersA but not in CustomersB (by CustomerID)
var query = customersA.Where(cA => !customersB.Any(cB => cB.Id == cA.Id)).ToList();
•customers in CustomersB also with the same CustomerID in CustomerA but different CustomerName
var query = customersB.Where(cB => customersA.Any(cA => cA.Id == cB.Id
&& cA.CustomerName != cB.CustomerName))
.ToList();

If you're planning on doing these comparisons in multiple places, you could also create a custom EqualityComparer<Customer> and re-use them wherever needed.
This is an example of two comparers, one based on Id and another based on Id and Name. I'm going to assume a customer id is unique in this example:
public sealed class CustomerByIdEqualityComparer : IEqualityComparer<Customer>
{
public bool Equals(Customer x, Customer y)
{
if (ReferenceEquals(x, y)) return true;
if (ReferenceEquals(x, null)) return false;
if (ReferenceEquals(y, null)) return false;
if (x.GetType() != y.GetType()) return false;
return x.CustomerId == y.CustomerId;
}
public int GetHashCode(Customer obj)
{
return obj.CustomerId;
}
}
public sealed class CustomerByIdAndNameEqualityComparer : IEqualityComparer<Customer>
{
public bool Equals(Customer x, Customer y)
{
if (ReferenceEquals(x, y)) return true;
if (ReferenceEquals(x, null)) return false;
if (ReferenceEquals(y, null)) return false;
if (x.GetType() != y.GetType()) return false;
return !string.Equals(x.CustomerName, y.CustomerName) &&
x.CustomerId == y.CustomerId;
}
public int GetHashCode(Customer obj)
{
return obj.CustomerId;
}
}
And you consume them using Enumerable.Except:
var comparerById = new CustomerByIdEqualityComparer();
var comparerByIdAndName = new CustomerByIdAndNameEqualityComparer();
var customerARelativeComplement = customersA.Except(customersB, comparerById);
var customerBRelativeComplement = customersB.Except(customersA, comparerById);
var customersBRelativeComplementByName = customersB
.Except(customersA, comparerByIdAndName);
If you're working with large sets, consider using HashSet<T> to do the filtering. Only problem with it is that you can only pass a single EqualityComparer<T> to it and you'll be bound to it.

select from Dictionary finds value but select from ConcurrentDictionary does not

Today i was doing some tests with the ConcurrentDictionary and Dictionary:
class MyTest
{
public int Row { get; private set; }
public int Col { get; private set; }
public string Value { get; private set; }
public MyTest(int row, int col, string value)
{
this.Col = col;
this.Row = row;
this.Value = value;
}
public override bool Equals(object obj)
{
MyTest other = obj as MyTest;
return base.Equals(other);
}
public override int GetHashCode()
{
return (Col.GetHashCode() ^ Row.GetHashCode() ^ Value.GetHashCode());
}
}
Using the Entity above i created and filled a ConcurrentDictionary and a Dictionary and tried the code below:
ConcurrentDictionary<MyTest, List<MyTest>> _test = new ConcurrentDictionary<MyTest, List<MyTest>>();
Dictionary<MyTest, List<MyTest>> _test2 = new Dictionary<MyTest, List<MyTest>>();
MyTest dunno = _test.Values.AsParallel().Select(x => x.Find(a => a.Col == 1 && a.Row == 1)).FirstOrDefault();
MyTest dunno2 = _test2.Values.AsParallel().Select(x => x.Find(a => a.Col == 1 && a.Row == 1)).FirstOrDefault();
The first one returns the value but the second one not, what am i doing wrong?
This is the code used to add the values:
_test.AddOrUpdate(cell10,
new List<MyTest>
{
new MyTest(1, 1, "ovpSOMEVALUEValue"),
new MyTest(1, 2, "ocpSOMEVALUEValue")
},
(key, value) => value = new List<MyTest>());
_test2.Add(cell10,
new List<MyTest>
{
new MyTest(1, 1, "ovpSOMEVALUEValue"),
new MyTest(1, 2, "ocpSOMEVALUEValue")
}
);

You are calling AddOrUpdate, and your third parameter is that it should create a new empty list, thus the result is that you end up with an empty list. I am guessing that somewhere before this line of code you are adding an entry with the same key.
Also notice that the Equals function is incorrect. You are comparing on reference, not on the actual values you use in the GetHashCode. I suggest you use the default template for overriding Equals:
protected bool Equals(x other) {
return Row == other.Row && Col == other.Col && string.Equals(Value, other.Value);
}
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj)) return false;
if (ReferenceEquals(this, obj)) return true;
if (obj.GetType() != this.GetType()) return false;
return Equals((x) obj);
}
public override int GetHashCode()
{
unchecked
{
var hashCode = Row;
hashCode = (hashCode*397) ^ Col;
hashCode = (hashCode*397) ^ (Value != null ? Value.GetHashCode() : 0);
return hashCode;
}
}