Cannot implicitly convert type 'System.Collections.Generic.IEnumerable<AnonymousType#1>' to 'System.Collections.Generic.List<modelClass> [duplicate]

Question

I am trying to populate Transaction data where AccountNumber does not exist. I need to access the Account table to get that. I am getting the following error where I am trying to return IEnumerable

Cannot implicitly convert type System.Collections.Generic.IEnumerable<AnonymousType#1> to System.Collections.Generic.List<ProjectModel.Transaction>

The error is shown on top of .ToList(); part of the code. What am I doing wrong?

the code is:

    public static IEnumerable<Transaction>GetAllTransactions()
    {
       List<Transaction> allTransactions = new List<Transaction>();
        using (var context = new CostReportEntities())
        {
            allTransactions = (from t in context.Transactions
                               join acc in context.Accounts on t.AccountID equals acc.AccountID
                               where t.AccountID == acc.AccountID
                               select new 
                               {
                                   acc.AccountNumber,
                                   t.LocalAmount
                               }).ToList();

        }
        return allTransactions;

    }

Answer 1

List of anonymous types cannot be casted to list of transactions. Looks like your Transaction class do not have AccountNumber property. Also you cannot return anonymous objects from methods. So you should create some type which will hold required data:

public class AccountTransaction
{
    public int LocalAmount { get; set; }
    public int AccountNumber { get; set; }
}

And return these objects:

public static IEnumerable<AccountTransaction> GetAllTransactions()
{       
    using (var context = new CostReportEntities())
    {
        return (from t in context.Transactions
                join acc in context.Accounts 
                     on t.AccountID equals acc.AccountID              
                select new AccountTransaction {
                     AccountNumber = acc.AccountNumber,
                     LocalAmount = t.LocalAmount
                }).ToList();
    }
}

BTW you don't need duplicate join condition in where filter

Answer 2

The anonymous type which you're projecting in the "select new" section of your Linq query cannot be casted directly to your "Transaction" type.

Instead, you should project a new instance of Transaction. The following might help:

allTransactions = (from t in context.Transactions
    join acc in context.Accounts on t.AccountID equals acc.AccountID
    where t.AccountID == acc.AccountID
    select new Transaction()
    {
        AccountNumber = acc.AccountNumber,
        LocalAmount = t.LocalAmount
    }).ToList();