Records are not being sorted

Question

I am trying to sort my records out in the jQuery jTable but it is not sorting the records. I am getting records from an excel file.

Here's the sorting bit of the code that I am trying to sort the records:

if (sorting != null)
{
 daa.OrderByDescending(i => i.Date);
}

Here's my full code for your inspection:

public JsonResult TopPlayedInVenueList1(string sorting, string StartDate = "", string EndDate = "", int jtStartIndex = 0, int jtPageSize = 0, string jtSorting = null)
    {
        try
        {

            if (Request.IsAuthenticated == true)
            {
                string Path = @"C:\\5Newwithdate-1k.xls";
                OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= '" + Path + "';Extended Properties=" + (char)34 + "Excel 8.0;IMEX=1;" + (char)34 + "");
                OleDbDataAdapter da = new OleDbDataAdapter("select * from [Sheet1$]", con);
                con.Close();
                System.Data.DataTable data = new System.Data.DataTable();
                da.Fill(data);

                List<TopPlayed> daa = new List<TopPlayed>();

                foreach (DataRow p in data.Rows)
                {
                    TopPlayed top = new TopPlayed()
                    {
                        TrackID = Convert.ToInt32(p.Field<double>("TrackID")),
                        Date = p.Field<DateTime>("DateTimes"),
                        TrackName = p.Field<string>("TrackName"),
                        ArtistName = p.Field<string>("ArtistName"),
                        Times = Convert.ToInt32(p.Field<double>("Times"))
                    };
                    daa.Add(top);
                }

                var listOrder = daa.Where(i => i.Date >= Convert.ToDateTime(StartDate) && i.Date <= Convert.ToDateTime(EndDate)).ToList();

                var newlist = listOrder.ToList().GetRange(jtStartIndex, jtPageSize);
                if (!string.IsNullOrWhiteSpace(sorting))
                {
                    newlist = listOrder.OrderByDescending(i => i.Date);
                }

                return Json(new { Result = "OK", Records = newlist, TotalRecordCount = listOrder.ToList().Count });

Before posting, I tried this and this examples but none of them worked.

To clarify, I am getting data from an excel file so that makes the List IEnumerable and not IQueryable right? Could you please kindly help out on this sorting issue. Thanks in advance.

Edit: Here's the updated code; Konrad

  if (sorting != null)
  {
    daa.OrderBy(i => i.Date);
  }
    var result = daa.OrderBy(i => i.Date);

Answer 1

This call:

daa.OrderBy(i => i.Date);

do not sort data in-place, you must save results into another variable:

var result = daa.OrderBy(i => i.Date);

Answer 2

What you're doing in your code needs a bit of attention:

public JsonResult TopPlayedInVenueList1(string sorting, string StartDate = "", string EndDate = "", int jtStartIndex = 0, int jtPageSize = 0, string jtSorting = null)
{
    try
    {

        if (Request.IsAuthenticated == true)
        {
            string Path = @"C:\\5Newwithdate-1k.xls";
            OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= '" + Path + "';Extended Properties=" + (char)34 + "Excel 8.0;IMEX=1;" + (char)34 + "");
            OleDbDataAdapter da = new OleDbDataAdapter("select * from [Sheet1$]", con);
            con.Close();
            System.Data.DataTable data = new System.Data.DataTable();
            da.Fill(data);

            List<TopPlayed> daa = new List<TopPlayed>();

            foreach (DataRow p in data.Rows)
            {
                TopPlayed top = new TopPlayed()
                {
                    TrackID = Convert.ToInt32(p.Field<double>("TrackID")),
                    Date = p.Field<DateTime>("DateTimes"),
                    TrackName = p.Field<string>("TrackName"),
                    ArtistName = p.Field<string>("ArtistName"),
                    Times = Convert.ToInt32(p.Field<double>("Times"))
                };

                //Don't sort inside your foreach!
                //if (sorting != null)
                //{
                //    daa.OrderBy(i => i.Date);
                //}

                daa.Add(top);
            }

            //var listOrder = daa.OrderBy(i => i.Date).ToList().Where(i => i.Date >= Convert.ToDateTime(StartDate) && i.Date <= Convert.ToDateTime(EndDate));
            //Don't run a Where after Orderby, probably you're fine...but not sure its guaruanteed, oh and you probably don't want to sort here either
            //I'm also a little surprised that the Convert statements in there aren't causing runtime errors..
            var listOrder = daa.Where(I => i.Date >= Convert.ToDateTime(StartDate) && i.Date <= Convert.ToDateTime(EndDate)).ToList();

            //you don't need to convert .ToList() to get .Count
            if (jtStartIndex + 150 > listOrder.ToList().Count)
            {
                int val = listOrder.ToList().Count - jtStartIndex;
                jtPageSize = val;
            }

            //This is the list that you actually return. This is where you sort your list
            var newlist = listOrder.OrderBy(i => i.Date).ToList().GetRange(jtStartIndex, jtPageSize);
            return Json(new { Result = "OK", Records = newlist, TotalRecordCount = listOrder.ToList().Count });

If I had to guess, your problem is that you're sorting in about four different places, and your sort is working, but you're just re-sorting it at the end so you think it's not working. Sort in only one location. If it's still not working, just put a breakpoint there and check the list yourself and see if it's sorting or not. Should be fairly easy to figure out.

It's a little hard to figure out from your code, but at the very bottom, this seems to be what you want (Not sure at this point if you want to order by descending or ascending, this is descending):

var newlist = listOrder.ToList().GetRange(jtStartIndex, jtPageSize);
if(!string.IsNullOrWhiteSpace(sorting))
{
  newlist = newlist.OrderByDescending(o => o.Date).ToList();
}

I'd take a moment to go through and make sure that you actually need all those ToList()'s in there also. Some look...unnecessary? Anyway, hopefully this helps you get your problem sorted out. Good Luck.