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c#linqgenericsienumerablemscorlib

cannot convert from IEnumerable<T> to IEnumerable<T>


I've been off in a world of front end programming lately, but am diving back into C# for a project I am working on. I am defining some of my models and generic functionality, and am getting the following error:

Error 3 Argument 2: cannot convert from 'System.Collections.Generic.IEnumerable<T> [c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.5\mscorlib.dll]' to 'System.Collections.Generic.IEnumerable<T> [c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.5\mscorlib.dll]'

The error is coming from the return statement in the following function:

public static PagedResult<T> Create<T, TEntity>(IOrderedQueryable<TEntity> query, PagedRequest pagedRequest, Func<TEntity, T> converter)
        where T : class
    {
        var count = query.Count();

        if (pagedRequest.SortInfo.Fields.Any())
        {
            var firstPass = true;
            foreach (var sortOrder in pagedRequest.SortInfo.Fields)
            {
                if (firstPass)
                {
                    firstPass = false;
                    query = sortOrder.Direction == SortDirection.Ascending
                                ? query.OrderBy(sortOrder.Field) :
                                  query.OrderByDescending(sortOrder.Field);
                }
                else
                {
                    query = sortOrder.Direction == SortDirection.Ascending
                                ? query.ThenBy(sortOrder.Field) :
                                  query.ThenByDescending(sortOrder.Field);
                }
            }
        }

        query = (IOrderedQueryable<TEntity>) query.Skip((pagedRequest.Page - 1) * pagedRequest.PageSize).Take(pagedRequest.PageSize);

        var list = new List<T>();
        foreach (var entity in query)
        {
            list.Add(converter(entity));
        }

        return Create(pagedRequest, list.AsEnumerable(), count);
    }

and the Create function:

static public PagedResult<T> Create(PagedRequest request, IEnumerable<T> data, long totalCount)
    {
        var result = new PagedResult<T> {Status = ResultStatus.Successful, Data = data.ToArray()};

        result.Count = result.Data.Count();
        result.TotalCount = totalCount;

        result.Page.Index = request.Page;
        result.Page.Size = request.PageSize;
        if (result.Page.Size > 0)
        { result.Page.Count = (long)Math.Ceiling((double)totalCount / result.Page.Size); }

        return result;
    }

Can't seem to get the compile time error to go away. Anybody have any ideas on how to fix this?


Solution

  • Thanks to @JeffMercado, the solution was very simple.

    The method signature for my second Create function needed to be:

    static public PagedResult<T> Create<T>(PagedRequest request, IEnumerable<T> data, long totalCount)
    

    instead of:

    static public PagedResult<T> Create(PagedRequest request, IEnumerable<T> data, long totalCount)