Make language switch working for blazor server side.

framework/src/Volo.Abp.AspNetCore.Components.Server.BasicTheme/Themes/Basic/LanguageSwitch.razor

@@ -0,0 +1,67 @@
+@using Volo.Abp.Localization
+@using System.Globalization
+@using System.Collections.Immutable
+@using Microsoft.AspNetCore.RequestLocalization
+@inject ILanguageProvider LanguageProvider
+@inject IJSRuntime JsRuntime
+@inject NavigationManager NavigationManager
+@inject IAbpRequestLocalizationOptionsProvider RequestLocalizationOptionsProvider
+@if (_otherLanguages != null && _otherLanguages.Any())
+{
+    <BarDropdown>
+        <BarDropdownToggle>
+            @_currentLanguage.DisplayName
+        </BarDropdownToggle>
+        <BarDropdownMenu RightAligned="true">
+            @foreach (var language in _otherLanguages)
+            {
+                <BarDropdownItem Clicked="() => ChangeLanguage(language)">@language.DisplayName</BarDropdownItem>
+            }
+        </BarDropdownMenu>
+    </BarDropdown>
+}
+@code {
+    private IReadOnlyList<LanguageInfo> _otherLanguages;
+    private LanguageInfo _currentLanguage;
+
+    protected override async Task OnInitializedAsync()
+    {
+        var languages = await LanguageProvider.GetLanguagesAsync();
+        var currentLanguage = languages.FindByCulture(
+            CultureInfo.CurrentCulture.Name,
+            CultureInfo.CurrentUICulture.Name
+            );
+        
+        if (currentLanguage == null)
+        {
+            var localizationOptions = await RequestLocalizationOptionsProvider.GetLocalizationOptionsAsync();
+            if (localizationOptions.DefaultRequestCulture != null)
+            {
+                currentLanguage = new LanguageInfo(
+                    localizationOptions.DefaultRequestCulture.Culture.Name,
+                    localizationOptions.DefaultRequestCulture.UICulture.Name,
+                    localizationOptions.DefaultRequestCulture.UICulture.DisplayName);
+            }
+            else
+            {
+                currentLanguage = new LanguageInfo(
+                    CultureInfo.CurrentCulture.Name,
+                    CultureInfo.CurrentUICulture.Name,
+                    CultureInfo.CurrentUICulture.DisplayName);
+            }
+        }
+
+        _currentLanguage = currentLanguage;
+        _otherLanguages = languages.Where(l => l != _currentLanguage).ToImmutableList();
+    }
+
+    private void ChangeLanguage(LanguageInfo language)
+    {
+        var relativeUrl = NavigationManager.Uri.RemovePreFix(NavigationManager.BaseUri).EnsureStartsWith('/');
+        
+        NavigationManager.NavigateTo(
+            $"/Abp/Languages/Switch?culture={language.CultureName}&uiCulture={language.UiCultureName}&returnUrl={relativeUrl}",
+            forceLoad: true
+        );
+    }
+}