How to filter a public IEnumerable with .Where?

Question

Very new to Net Core and CSharp, I am trying to filter a list before it posts proposalVM.ProposalCategoryList = _unitOfWork.ProposalCategory.GetAll().OrderBy(s => s.ProposalCategoryName) .Where(s => s.ProposalCategoryName != "Freight") .Select(i => new SelectListItem { Text = i.ProposalCategoryName, Value = i.ProposalCategoryId.ToString() }); I don't get an error but neither does it filter the list. Any help is gratefully received.

Sachin Singh · Answer

test this proposalVM.ProposalCategoryList = _unitOfWork.ProposalCategory.GetAll().Where(s => s.ProposalCategoryName != "Freight" ).OrderBy(s => s.ProposalCategoryName).Select(i => new SelectListItem { Text = i.ProposalCategoryName, Value = i.ProposalCategoryId.ToString() });

Nicholas Mabe · Answer

Hi Sachin, thank you for you help. It didn't quite work but helped point me in the right direction. My operators where incorrect. Both the following examples now filter: ProposalCategoryList = _unitOfWork.ProposalCategory.GetAll().OrderBy(s => s.ProposalCategoryName).Where(s => s.ProposalCategoryName == "Freight").Select(i => new SelectListItem ProposalCategoryList = _unitOfWork.ProposalCategory.GetAll().OrderBy(s => s.ProposalCategoryName).Where(ProposalCategory => ProposalCategory.ProposalCategoryId == 29).Select(i => new SelectListItem

Nicholas Mabe · Answer

Hi Nikunji, thanks for the reply. Unfortunately the solution did not filter the dropdown, here the other elements you mentioned: Controller: ProposalController.cs ViewModel:ProposalVM.cs Repository: ProposalRepository.cs View: Upsert.cshtml ProposalRepository.cs namespace MEVASALES.DataAccess.Repository { public class ProposalRepository : Repository , IProposalRepository { private readonly ApplicationDbContext _db; public ProposalRepository(ApplicationDbContext db) : base (db) { _db = db; } public void Update(Proposal proposal) { var objFromDb = _db.Proposals.FirstOrDefault(s => s.ProposalId == proposal.ProposalId); if (objFromDb != null ) { objFromDb.ProposalDate = proposal.ProposalDate; objFromDb.ProposalReference = proposal.ProposalReference; objFromDb.ProposalCategoryId = proposal.ProposalCategoryId; _db.SaveChanges(); } } } } ProposalVM.cs using Microsoft.AspNetCore.Mvc.Rendering; using System; using System.Collections.Generic; using System.Text; namespace MEVASALES.Models.ViewModels { public class ProposalVM { public Proposal Proposal { get ; set ; } public IEnumerable ProposalCategoryList { get ; set ; } ProposalController.cs public IActionResult Upsert( int ? id) { ProposalVM proposalVM = new ProposalVM() { Proposal= new Proposal(), ProposalCategoryList = _unitOfWork.ProposalCategory.GetAll().OrderBy(s => s.ProposalCategoryName) .Where(s => s.ProposalCategoryName != "Freight" ).Select(i => new SelectListItem { Text = i.ProposalCategoryName, Value = i.ProposalCategoryId.ToString() }) }; if (id == null ) { //this is for create return View(proposalVM); } //this is for edit proposalVM.Proposal = _unitOfWork.Proposal.Get(id.GetValueOrDefault()); if (proposalVM.Proposal == null ) { return NotFound(); } return View(proposalVM); } Upsert.cshtml @model MEVASALES.Models.ViewModels.ProposalVM @{ Layout = "~/Views/Shared/_Layout.cshtml" ; var title = "Create Proposal" ; } "post" > class = "row p-3 border" > "ModelOnly" class = "text-danger" > "hidden" asp- for = "Proposal.ProposalId" /> @ if (Model.Proposal.ProposalId != 0) { //edit title = "Edit Proposal" ; } class = "col-12 border-bottom" > class = "text-primary" >@title class = "col-8 pt-4" > class = "form-group row" > class = "col-4" > for = "Proposal.ProposalReference" > class = "col-8" > for = "Proposal.ProposalReference" class = "form-control" /> for = "Proposal.ProposalReference" class = "text-danger" > class = "form-group row" > class = "col-4" > Category class = "col-8" > @Html.DropDownListFor(m => m.Proposal.ProposalCategoryId, Model.ProposalCategoryList, "--Select a Category--" , new { @ class = "form-control" }) for = "Proposal.ProposalCategoryId" class = "text-danger" > class = "form-group row" > class = "col-4" > for = "Proposal.ProposalDate" > class = "col-8" > for = "Proposal.ProposalDate" class = "form-control date-input" /> for = "Proposal.ProposalDate" class = "text-danger" > class = "form-group row" > class = "col-8 offset-4" > @ if (Model.Proposal.ProposalId != 0) { "_EditAndBackToListButton" model= "Model.Proposal.ProposalId" /> } else { "_CreateAndBackToListButton" /> } } } return View(proposalVM); }

Nikunj Satasiya · Answer

Hi Nicholas, Please try this solution. But Before Implement, this solution checks the following points first. 1) _unitOfWork.ProposalCategory. GetAll() return value or returnig null value? 2) proposalVM.ProposalCategoryList is IEnumerable ? Solution proposalVM.ProposalCategoryList = (from txt in _unitOfWork.ProposalCategory.GetAll().Where(s => s.ProposalCategoryName != "Freight").OrderBy(s => s.ProposalCategoryName) .AsEnumerable() select new SelectListItem() { Text = txt.Description, Value = txt.Id.ToString() }); Thank you.

How to filter a public IEnumerable<SelectListItem> with .Where?

Answers (4)