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无法从IEnumerable <T>转换为IEnumerable <T>

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我最近一直处于前端编程的世界,但我正在为我正在进行的项目重新回到C# . 我正在定义我的一些模型和通用功能,并收到以下错误:

错误3参数2:无法从'System.Collections.Generic.IEnumerable <T> [c:\ Program Files(x86)\ Reference Assemblies \ Microsoft \ Framework.NETFramework \ v4.5 \ mscorlib.dll]'转换为' System.Collections.Generic.IEnumerable <T> [c:\ Program Files(x86)\ Reference Assemblies \ Microsoft \ Framework.NETFramework \ v4.5 \ mscorlib.dll]'

错误来自以下函数中的return语句:

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);
    }

和创建功能:

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;
    }

似乎无法让编译时错误消失 . 有人对如何解决这个问题有任何想法吗?

1 回答

  • 0

    感谢@JeffMercado,解决方案非常简单 .

    我的第二个Create函数的方法签名需要是:

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

    代替:

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

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