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c# Getting the Index from an array inside a JSon Object

I'm trying to find out the index of a string in an array within a JObject object. For example, you could give frc610 and it would return 0.
// Get rankings JSON file from thebluealliance.com
string TBArankings = #"https://www.thebluealliance.com/api/v2/district/ont/2017/rankings?X-TBA-App-Id=frc2706:ONT-ranking-system:v01";
var rankings = new WebClient().DownloadString(TBArankings);
string usableTeamNumber = "frc" + teamNumberString;
string team_key = "";
int rank = 0;
dynamic arr = JsonConvert.DeserializeObject(rankings);
foreach (dynamic obj in arr)
{
team_key = obj.team_key;
rank = obj.rank;
}
int index = Array.IndexOf(arr, (string)usableTeamNumber); // <-- This is where the exception is thrown.
Console.WriteLine(index);
// Wait 20 seconds
System.Threading.Thread.Sleep(20000);
Here's the json file I'm using.
I've tried multiple different solutions, none of which worked.

You could just keep the index in variable.
string usableTeamNumber = $"frc{teamNumberString}";
string team_key = "";
int rank = 0;
int index = 0;
int count = 0;
dynamic arr = JsonConvert.DeserializeObject(rankings);
foreach (dynamic obj in arr)
{
team_key = obj.team_key;
rank = obj.rank;
if (usableTeamNumber.Equals(team_key) {
index = count;
}
count++;
}
Console.WriteLine(index);

Create a class that mimics your data structure, like such (only has 3 of the root fields):
public class EventPoints
{
public int point_total { get; set; }
public int rank { get; set; }
public string team_key { get; set; }
}
Then you can Deserialize the object into a list of those objects and you can use LINQ or other tools to query that list:
string teamNumberString = "frc2056";
string TBArankings = #"https://www.thebluealliance.com/api/v2/district/ont/2017/rankings?X-TBA-App-Id=frc2706:ONT-ranking-system:v01";
var rankings = new WebClient().DownloadString(TBArankings);
List<EventPoints> eps = JsonConvert.DeserializeObject<List<EventPoints>>(rankings);
EventPoints sp = eps.Where(x => x.team_key.Equals(teamNumberString)).FirstOrDefault();
Console.WriteLine(eps.IndexOf(sp));
Console.ReadLine();

Is there a way to replace an object which is referenced in multiple lists with a new instance easily?

I would like to replace an object which is referenced in multiple lists with a new instance of matching interface class.
Here is an example to better understand the problem.
There is an interface called IPosition
There are two classes that implement that interface: RealPosition and AccessiblePosition
In my algorithm I am receiving an array of IPosition list, like this: List<IPosition>[], basically multiple lists
It is very common that the lists reference the same instance of an object. Here is a visualisation:
Now I would like to create a new instance of the AccessiblePosition class and update all references in all lists.
Is there a way to do that easily?
Many thanks in advance!

You can create a container for your data.
public interface IContainer<T>
{
T Data { get; set; }
}
And a List<IContainer<IPosition>>.
Now you can change Data of a container instead of changing item references.

You could just iterate through the lists and compare the items.
public interface IPosition
{
int ID { get; set; }
}
public class RealPosition : IPosition
{
public int ID { get; set; }
}
public class AccessiblePosition : IPosition
{
public int ID { get; set; }
}
void Main()
{
var toReplace = new RealPosition { ID = 1 };
var list1 = new List<IPosition>
{
toReplace,
new RealPosition { ID = 2 },
new RealPosition { ID = 3 },
};
var list2 = new List<IPosition>
{
toReplace,
new RealPosition { ID = 4 },
new RealPosition { ID = 5 },
};
var listOfLists = new List<List<IPosition>>{ list1, list2 };
var replacement = new AccessiblePosition{ ID = 42 };
foreach(var list in listOfLists)
{
//must use for here
for(int i = 0; i < list.Count; ++i)
{
if(list[i] == toReplace)
{
list[i] = replacement;
}
}
}
}

list values changes when dataset iteration

I have List of type Date_Check ,I execute a sql query and retrieve the values in a dataset
and I populate the List by iterate through the dataset ,the problem is that when the second iteration towards the list[0],list[1],list[2]... values got the replaced by current object values
Here is my code :
string query = "select Record_Id, Movie_Name from tbl_theater_master ";
DataSet dtst_Theatrs = new DataSet();
dtst_Theatrs = ObjCommon.GetObject.ExecuteQuery_Select(Connection.ConnectionString, query);
if (dtst_Theatrs.Tables[0].Rows.Count != 0)
{
List<Date_Check> lst_Date_Check = new List<Date_Check>();
Date_Check obj_Date_Check = new Date_Check();
for (int i = 0; dtst_Theatrs.Tables[0].Rows.Count > i; i++)
{
obj_Date_Check.Movie_Name = dtst_Theatrs.Tables[0].Rows[i]["Movie_Name"].ToString();
obj_Date_Check.Record_Id = dtst_Theatrs.Tables[0].Rows[i]["Record_Id"].ToString();
lst_Date_Check.Add(obj_Date_Check);
}
}
Here is my Date_Check object :
public class Date_Check
{
public string Record_Id { get; set; }
public string Movie_Name { get; set; }
}
When dataset iteration is completed the lst_Date_Check got all the indexes changed to the Last iterations values ,what's wrong with my code

Keep creation of the object of the class Date_Check obj_Date_Check = new Date_Check(); inside the for-loop. That's how you make new object on every iteration.
for (int i = 0; dtst_Theatrs.Tables[0].Rows.Count > i; i++)
{
Date_Check obj_Date_Check = new Date_Check();
obj_Date_Check.Movie_Name = dtst_Theatrs.Tables[0].Rows[i]["Movie_Name"].ToString();
obj_Date_Check.Record_Id = dtst_Theatrs.Tables[0].Rows[i]["Record_Id"].ToString();
lst_Date_Check.Add(obj_Date_Check);
}

This is because your Date_Check object is a reference type and not a value type. This means the line Date_Check obj_Date_Check = new Date_Check(); creates the variable in memory once and from then on every time update that object you are updating the same single object. You have 2 options:
Instantiate the object inside the for loop to create a single object in memory to work with i.e:
for (int i = 0; dtst_Theatrs.Tables[0].Rows.Count > i; i++)
{
Date_Check obj_Date_Check = new Date_Check();
obj_Date_Check.Movie_Name = dtst_Theatrs.Tables[0].Rows[i]["Movie_Name"].ToString();
obj_Date_Check.Record_Id = dtst_Theatrs.Tables[0].Rows[i]["Record_Id"].ToString();
lst_Date_Check.Add(obj_Date_Check);
}
Or create your Date_Check object as a Value Type by using a Struct i.e:
public struct Date_Check
{
public string Record_Id { get; set; }
public string Movie_Name { get; set; }
}

Get string value and add to specific variables

I want to get the value in an array and i want to put it in a variable
This is the array {1,eli}
CsvValues = RowData.Split(new string[] {","},
StringSplitOptions.RemoveEmptyEntries); // RowData is {1,eli}
List<string> elements = new List<string>();
foreach (string data in CsvValues)
{
elements.Add(data);
}
and then I want to put it here:
result.Add(new wsSample()
{
id = elements[0],
name = elements[1]
});
How will i add the elements value to id and name?
public class wsSample
{
[DataMember]
public string id { get; set; }
[DataMember]
public string name { get; set; }
}

How is the rest of the input array structured?
If it is elements = {"1","eli", "2","manning"}
then you might be better off using a for loop.
I think this is what you are looking for
List<wsSample> samples = new List<wsSample>();
for(int i=0; i< elements.length-1; ++i)
{
samples.Add(new wsSample()
{
id = elements[i]
name = elements[i+1]
});
i= i+2;
}

C# Linq "Entity with the same key '0' already added." when inserting multiple rows

I am trying to insert data in bulk, database is MySQL connection is done using Devart LinqConnect.
Here is a code:
DataContext db = new DataContext();
List<XYData> XYDList = new List<XYData>(); // Data Type
List<xydata> xyToBeInsrted = new List<xydata>(); // Database table
XYDList = XYData.genXYData(12, 1234); // Generates 12 example records
foreach (XYData oneXY in XYDList)
{
// Create clear row representation
xydata xy_row = new xydata();
// Assign data from object
xy_row.id = oneXY.Id;
xy_row.Batchid = (int)oneXY.BatchId;
xy_row.Ch = oneXY.Channel;
xy_row.Value = oneXY.Value;
xy_row.Pos = (int)oneXY.Position;
xy_row.Dtm = oneXY.Time;
// Add to list of rows to be inserted
xyToBeInsrted.Add(xy_row);
}
db.xydatas.InsertAllOnSubmit<xydata>(xyToBeInsrted);
db.SubmitChanges();
Last line gives an error "Entity with the same key '0' already added."
When I lower number of items to be generated to 1 then it works. Anything above 1 gives error.
Table has set Auto Increment on record Id field.
Trying to solve that for 2 hours without success.
EDIT:
Data Class:
public class XYData
{
[Column(IsPrimaryKey = true, IsDbGenerated = true)]
public int Id { get; set; }
public int BatchId { get; set; }
public int Channel { get; set; }
public String Value { get; set; }
public double Position { get; set; }
public DateTime Time { get; set; }
private static Random rand = new Random();
public XYData(int channel = 0, string val = "")
{
Channel = channel;
Value = val;
Position = 0;
Time = DateTime.Now;
}
public static List<XYData> genXYData(int howMany, int batchId)
{
List<XYData> _allXYData = new List<XYData>();
for (int i = 0; i < howMany; i++)
{
XYData _singleXY = new XYData();
_singleXY.BatchId = batchId;
for (int j = 64 * (1 << i); j > 0; j--)
{
uint k = (uint)rand.Next(int.MaxValue);
_singleXY.Value += k.ToString("X8");
}
_allXYData.Add(_singleXY); // Add to list
}
return _allXYData; // Return list of generated data.
}
}

Something like this may be needed on your model definition -
[Column(IsPrimaryKey=true, IsDbGenerated=true)]
public int Id { get; set; }
http://www.devart.com/linqconnect/docs/PrimaryKeyMapping.html