asp.net core distinct selectlistitem not working properly

Marius Vasile

5y1.6k.NET

I am trying to list distinct values in a SelectListItem but it is not working. Any ideeas?

HazardSourceList = await _context.RiskAssessmentsMain.Where(s => s.OrgID == orgid).Select(s =>
                                                    new SelectListItem
                                                    {

                                                        Value = s.IdRA.ToString(),
                                                        Text = s.HazSource

                                                    }).Distinct().ToListAsync();

3 Replies

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Marius Vasile5y ago
I managed to make it work by eliminating the Value from the SelectListItem. Is it wrong to use as a parameter the text value?

For example
$(function () {
            $("#HazSource").on("change", function () {
                var data = $("#HazSource :selected").text();
                $("#shs").val(data);
                $('#FilterSource').submit();
            });
        });
0
Marius Vasile5y ago
I have the same result with the solution proposed by you. I got the ideea, I will try different
0
Sachin Singh5y ago
Distinct Doesn't work for reference types until you override the Equals() method of a class or implement IEqualityComparer.
The best solution to override the Equals method is to project anonymous types.
var res= await _context.RiskAssessmentsMain.Select(x => new { x.IdRA, x.HazSource}).Distinct().ToListAsync();

HazardSourceList=res.Where(s => s.OrgID == orgid).Select(s => new SelectListItem
                     {

                           Value = s.IdRA.ToString(),
                           Text = s.HazSource

                      }).ToList();
0