Question

我是一名相当初级的C＃开发人员，请原谅我这很容易。我在点击表格列标题时尝试按ASC和DESC顺序对数据进行排序，但出于某种原因，它没有这样做。

以下是您检查的分类代码：

if (sorting != null)
                {
                    if (sorting.Equals("TrackID ASC"))
                    {
                        daa.OrderBy(p => p.TrackID);
                    }
                    else if (sorting.Equals("TrackID DESC"))
                    {
                        daa.OrderByDescending(p => p.TrackID);
                    }
                    if (sorting.Equals("TrackName ASC"))
                    {
                        daa.OrderBy(p => p.TrackName);
                    }
                    else if (sorting.Equals("TrackName DESC"))
                    {
                        daa.OrderByDescending(p => p.TrackName);
                    }
                    else if (sorting.Equals("DateTimes ASC"))
                    {
                        daa.OrderBy(p => p.Date);
                    }
                    else if (sorting.Equals("DateTimes DESC"))
                    {
                        daa.OrderByDescending(p => p.Date);
                    }
                    else if (sorting.Equals("ArtistName ASC"))
                    {
                        daa.OrderBy(p => p.ArtistName);
                    }
                    else if (sorting.Equals("ArtistName DESC"))
                    {
                        daa.OrderByDescending(p => p.ArtistName);
                    }
                    else if (sorting.Equals("Times ASC"))
                    {
                        daa.OrderBy(p => p.Times);
                    }
                    else if (sorting.Equals("Times DESC"))
                    {
                        daa.OrderByDescending(p => p.Times);
                    }
                }

有人可以解释为什么它不起作用，我该如何解决并实现它以ASC和DESC顺序对数据进行排序？

任何帮助都会很棒:)谢谢

Answer 1

如果我没记错，方法“OrderBy”和“OrderByDescending”不会对直接调用它们的对象进行排序。相反，他们返回IOrderedEnumerable＆lt;对象＆gt;集合所以你需要自己使用IOrderedEnumerable作为参考对daa集合进行排序，或者从IOrderedEnumerable创建集合类型并将其分配给daa。当然刷新ui。

Answer 2

if (sorting != null)
                {
                    if (sorting.Equals("TrackID ASC"))
                    {
                       daa = daa.OrderBy(p => p.TrackID).ToList();
                    }
                    else if (sorting.Equals("TrackID DESC"))
                    {
                      daa =  daa.OrderByDescending(p => p.TrackID).ToList();
                    }
                    if (sorting.Equals("TrackName ASC"))
                    {
                     daa =   daa.OrderBy(p => p.TrackName).ToList();
                    }
                    else if (sorting.Equals("TrackName DESC"))
                    {
                      daa =  daa.OrderByDescending(p => p.TrackName).ToList();
                    }
                    else if (sorting.Equals("DateTimes ASC"))
                    {
                       daa = daa.OrderBy(p => p.Date).ToList();
                    }
                    else if (sorting.Equals("DateTimes DESC"))
                    {
                      daa =  daa.OrderByDescending(p => p.Date).ToList();
                    }
                    else if (sorting.Equals("ArtistName ASC"))
                    {
                       daa = daa.OrderBy(p => p.ArtistName).ToList();
                    }
                    else if (sorting.Equals("ArtistName DESC"))
                    {
                      daa =  daa.OrderByDescending(p => p.ArtistName).ToList();
                    }
                    else if (sorting.Equals("Times ASC"))
                    {
                      daa =  daa.OrderBy(p => p.Times).ToList();
                    }
                    else if (sorting.Equals("Times DESC"))
                    {
                      daa =  daa.OrderByDescending(p => p.Times).ToList();
                    }
                }

尝试一次。

表列标题不对数据进行排序

2 个答案: