public class SyncfusionLocalizer : ISyncfusionStringLocalizer
    {
        // To get the locale key from mapped resources file
        public string GetText(string key)
        {
            return this.ResourceManager.GetString(key);
        }

        // To access the resource file and get the exact value for locale key

        public System.Resources.ResourceManager ResourceManager
        {
            get
            {
                return ApplicationNamespace.Client.Resources.SfResources.ResourceManager;
            }
        }
    }

#region Localization
// Register the Syncfusion locale service to customize the  SyncfusionBlazor component locale culture
builder.Services.AddSingleton(typeof(ISyncfusionStringLocalizer), typeof(Shared.SyncfusionLocalizer));

// Set the default culture of the application
CultureInfo.DefaultThreadCurrentCulture = new CultureInfo("en-NZ");
CultureInfo.DefaultThreadCurrentUICulture = new CultureInfo("en-NZ");

// Get the modified culture from culture switcher
var host = builder.Build();
var jsInterop = host.Services.GetRequiredService<IJSRuntime>();
var result = await jsInterop.InvokeAsync<string>("cultureInfo.get");
if (result != null)
{
	// Set the culture from culture switcher
	var culture = new CultureInfo(result);
	CultureInfo.DefaultThreadCurrentCulture = culture;
	CultureInfo.DefaultThreadCurrentUICulture = culture;
}
#endregion

@using  System.Globalization
@inject IJSRuntime JSRuntime
@inject NavigationManager NavigationManager
@using Syncfusion.Blazor.DropDowns

<div>
    <SfDropDownList TValue="string" TItem="Cultures" DataSource="@CultureList" Width="143px" Index="@cultureIndex" PopupWidth="143px" CssClass="localization-combo">
        <DropDownListEvents TValue="string" TItem="Cultures" ValueChange="OnSelected"></DropDownListEvents>
        <DropDownListFieldSettings Value="Code" Text="Text"></DropDownListFieldSettings>
    </SfDropDownList>
</div>

@code {
    private int cultureIndex { get; set; }
    protected override async Task OnInitializedAsync()
    {

        switch (System.Globalization.CultureInfo.CurrentCulture.Name)
        {
            case "en-NZ":
                this.cultureIndex = 0;
                break;
            case "en-US":
                this.cultureIndex = 1;
                break;
        }

        await base.OnInitializedAsync();
    }

    private CultureInfo[] supportedCultures = new[]
    {
        new CultureInfo("en-NZ"),
        new CultureInfo("en-US")
    };

    private CultureInfo Culture
    {
        get => CultureInfo.CurrentCulture;
        set
        {
            if (CultureInfo.CurrentCulture != value)
            {
                var js = (IJSInProcessRuntime)JSRuntime;
                js.InvokeVoid("cultureInfo.set", value.Name);

                NavigationManager.NavigateTo(NavigationManager.Uri, forceLoad: true);
            }
        }
    }

    private void OnSelected(Syncfusion.Blazor.DropDowns.ChangeEventArgs<string, Cultures> e)
    {
        switch ((string)e.Value)
        {
            case "en-NZ":
                this.cultureIndex = 0;
                break;
            case "en-US":
                this.cultureIndex = 1;
                break;
        }
        Culture = new CultureInfo((string)e.Value);
    }

    List<Cultures> CultureList = new List<Cultures>
    {
        new Cultures() { Text = "English (en-NZ)", Code = "en-NZ" },
        new Cultures() { Text = "English (en-US)", Code = "en-US" },
    };

    public class Cultures
    {
        public string Text { get; set; }
        public string Code { get; set; }
    }
}

.localization-combo {
    border-radius: 4px;
    border-color: #B3B3B3;
    font-family: OpenSans-Regular;
    font-size: 12px;
    background-color: #FFFFFF;
    border-width: 1px;
    color: #333333;
}