Sorted Dictionary and List<>() has an error in VS 2010

Question

I have a code , i get it from my question from stack overflow

# Read data
var data = new SortedDictionary<(string id, string idr, string email), 
    List<(string reference, decimal amount)>>();

using (var input = File.OpenText("input.txt"))
{
    List<(string reference, decimal amount)> currentInvoice = null;

    for (var line = input.ReadLine(); line != null; line = input.ReadLine())
    {
        var fields = line.Split(new char[] { '@' }, 6);
        switch (fields.Length)
        {
            case 2:
                // Sanitize input
                if (fields[0] != "INV")
                {
                    throw new Exception("Unknown record type.");
                }
                if (currentInvoice == null)
                {
                    throw new Exception("Invoice without context.");
                }

                // Parse
                var invoiceEntry = fields[1].Split(new char[] { ' ' }, 
                    StringSplitOptions.RemoveEmptyEntries);

                if (invoiceEntry.Length == 2)
                {
                    decimal amount;
                    if (decimal.TryParse(invoiceEntry[1],
                        NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands,
                        CultureInfo.InvariantCulture,
                        out amount))
                    {
                        currentInvoice.Add((invoiceEntry[0], amount));
                    }
                }

                break;

            case 6:
                var currentContext = (id: fields[0], idr: fields[2], email: fields[5]);
                if (!data.TryGetValue(currentContext, out currentInvoice))
                {
                    currentInvoice = new List<(string reference, decimal amount)>();
                    data.Add(currentContext, currentInvoice);
                }
                break;

            default:
                throw new Exception("Unknown record.");
        }
    }
}

SortedDictionary can't be used it says

' using system.collection.generic.sorteddictionary<TKey,TValue> requires 2 agruments '

the List<(string reference, decimal amount)> currentInvoice = null ; has an error too , it says

'Only assignment,call,increment, decrement, new object expression can be used as a statement'

how to fix this?

Am i missing something here? there is no error with this code in my environment (though thats not to say there is not other issues) — TheGeneral, Oct 17 '19 at 01:48
@TheGeneral hmm im sure you're not missing something , i dont know why this code error , the SortedDictionary function cannot be used , and i dont know why .. — trytocode, Oct 17 '19 at 01:50
The compiler on VS2017 tells me: *Impossible de définir une classe ou un membre qui utilise des tuples, car le type 'System.Runtime.CompilerServices.TupleElementNamesAttribute' nécessaire au compilateur est introuvable. Une référence est-elle manquante ?* => ? — , Oct 17 '19 at 02:02
Is there anyway to fix this? And i cant understand the language sorry — trytocode, Oct 17 '19 at 02:03
@Olivier I think in the past you had to include the `System.ValueTuple` package from NuGet. — ProgrammingLlama, Oct 17 '19 at 02:03
@Enrico It says "It's impossible to define a class or member which uses tuples, because the type System.RunTime.CompilerServices.TupleElementNamesAttribute necessary to compile couldn't be found. Are you missing a reference?" - it's not exactly relevant to your situation. You said that you're using Visual Studio 2010, which I thinks limits you to an older version of the .NET Framework (4.0?) which doesn't support value tuples (introduced in 4.7). — ProgrammingLlama, Oct 17 '19 at 02:04
So i cant use this code .. okay thankyou i will find another way to clear my task , thanks for the help — trytocode, Oct 17 '19 at 02:06
@TheGeneral hehe i want too , but Office PC only has this IDE and i think i must work with my laptop to fix this task .. — trytocode, Oct 17 '19 at 02:07
You could use a custom class with three string properties instead of the tuple, if that's the issue. — Rufus L, Oct 17 '19 at 02:12

score 3 · Accepted Answer · edited Oct 28 '19 at 23:16

For an older version of Visual Studio you may be able to fix this by installing the following from nuget

_{Note : Take notice of the dependency, you may need to install an older version that supports your targeted framework}

It also should be noted, that if you are using VS 2010, it's time to tell your bosses/managers to upgrade, or use the community version.

Sorted Dictionary and List<>() has an error in VS 2010

1 Answers1