Duplicate item on dropdownlist anomaly when using preselected item.

Question

I have this issue on my SfDropdownlist when using a preselected item the dropdown items will duplicate/add the preselected item on the list. I need help how to fix this. My Oninitialized Code: private string selectedCompanyValue = string.Empty; private string selectedYearValue = string.Empty; protected override async Task OnInitializedAsync() { // Load companies and preselect first item company = (await CompanyService.CompanyList()).ToList(); if (company.Any()) { selectedCompanyValue = company.First().CompanyID.ToString(); } // Load years and preselect first item year = (await YearService.GetYears()).ToList(); if (year.Any()) { selectedYearValue = year.First().YearID.ToString(); } // Load initial grid data if selections exist if (!string.IsNullOrEmpty(selectedYearValue)) { await LoadData(); } }My SfDropdownlist Code:

Load Data

Attached are the photos of the issue regarding the duplicate items on the list. I can confirm on my Database that there are no duplicates.OliverAttachment: projectcode_ca6d46d9.zip

Yohapuja Selvakumaran · Answer

Hi Oliver,Thank you for reaching out to us.We have reviewed your query regarding duplicate data
appearing in the component, and we've created a runnable sample based on the
code snippet you shared. After thorough testing on our end, we were unable to
reproduce the issue — the data appears as expected without any duplicates. To help us investigate this further and accurately replicate
the issue in your environment, we kindly request the following details:
 A
     runnable sample from your end where the issue can be observed.
 A
     video recording or screenshot that demonstrates the duplicate data
     issue, if possible.
 The
     Syncfusion package version you are currently using in your project.
These details will help us narrow down the cause and provide
you with a prompt and effective solution.We’ve also attached the sample we created for your
reference. Please feel free to compare it with your implementation and let us
know if there are any specific differences or scenarios we might be
overlooking.We appreciate your cooperation and look forward to resolving
this with you.Regards,Yohapuja SAttachment: Dropdown_Duplicate_65904414.zip

oliver tejada · Answer

Thanks for the reply. I noticed your sample code for selectedCompanyValue and selectedYearValue is string. Mine in Int. I converted mine to string but the anomaly still exists. I'm attaching the video regarding the anomaly.Below is my updated code Home.razor page:@page "/"@using Microsoft.AspNetCore.Components.Server.ProtectedBrowserStorage@using Syncfusion.Blazor.Grids@using System.Dynamic@using Syncfusion.Blazor.DropDowns@rendermode InteractiveServer@inject ICompanyService CompanyService@inject IYearService YearService@inject DepreciationService DepreciationService@inject IJSRuntime Js@inject NavigationManager NavigationManager@inject ProtectedSessionStorage ProtectedSessionStorageAsset Depreciation Expense

Asset Depreciation Expense

Apply Filter

@if (!Records.Any()){

No depreciation records found for the selected year.

}@code { private List company = new(); // Use List instead of IEnumerable private List year = new(); // Use List instead of IEnumerable private int SelectedCompanyId; private int SelectedYearId; private IEnumerable Records = Enumerable.Empty(); private string selectedCompanyValue = string.Empty; private string selectedYearValue = string.Empty; private int userIdResult = 0; private string userNameResult = string.Empty; private bool isInteropExecuted = false; protected override async Task OnInitializedAsync() { // Load companies and preselect first item company = (await CompanyService.CompanyList()).ToList(); if (company.Any()) { selectedCompanyValue = company.First().CompanyID.ToString(); } // Load years and preselect first item year = (await YearService.GetYears()).ToList(); if (year.Any()) { selectedYearValue = year.First().YearID.ToString(); } // Load initial grid data if selections exist Records = await DepreciationService.GetDepreciationData(SelectedCompanyId, DateTime.Today.Year); } public Task OnChange(Syncfusion.Blazor.DropDowns.ChangeEventArgs args) { this.SelectedCompanyId = args.ItemData.CompanyID; selectedCompanyValue = args.Value; return Task.CompletedTask; } public Task OnChangeYear(Syncfusion.Blazor.DropDowns.ChangeEventArgs args) { this.SelectedYearId = args.ItemData.YearID; selectedYearValue = args.Value; return Task.CompletedTask; } public async Task LoadData() { Records = await DepreciationService.GetDepreciationData(SelectedCompanyId, SelectedYearId); }}My CompanyList Service: public async Task> CompanyList() { IEnumerable companies; using var conn = new SqlConnection(_configuration.Value); companies = await conn.QueryAsync("spCompany_List", commandType: CommandType.StoredProcedure); return companies; }My Year Service: public async Task> GetYears() { IEnumerable years; using var conn = new SqlConnection(_configuration.Value); years = await conn.QueryAsync("spCombobox_DepreciationDate", commandType: CommandType.StoredProcedure); return years; }My Storedprocedures: Attachment: 20250412_112328_b3bfce3e.zip

Malini Selvarasu · Answer

Hi Oliver,Thank
you for sharing the code snippet.We
have validated the reported issue based on the provided code and created a
sample for verification. However, we were unable to reproduce the issue — we
did not observe any duplicate data in our testing.Additionally,
we also attempted to modify the code by converting values to int, but even with
those changes, the issue did not occur at our end. For
your reference, we have attached the sample we used during our validation. We
kindly request you to review it and let us know if there are any specific steps
or conditions we might have missed that could help us replicate the issue on
our side. And can you please modify the shared sample to replicate the reported
issue at our end.Regards,Yohapuja
SAttachment: Dropdown_duplicate_Data_99fb32ea.zip