diff --git a/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Messages/UiMessageEventArgs.cs b/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Messages/UiMessageEventArgs.cs
index adae13a4c2..45bb66aaac 100644
--- a/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Messages/UiMessageEventArgs.cs
+++ b/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Messages/UiMessageEventArgs.cs
@@ -5,7 +5,7 @@ namespace Volo.Abp.AspNetCore.Components.Messages;
 
 public class UiMessageEventArgs : EventArgs
 {
-    public UiMessageEventArgs(UiMessageType messageType, string message, string title, UiMessageOptions options)
+    public UiMessageEventArgs(UiMessageType messageType, string message, string? title, UiMessageOptions options)
     {
         MessageType = messageType;
         Message = message;
@@ -13,7 +13,7 @@ public class UiMessageEventArgs : EventArgs
         Options = options;
     }
 
-    public UiMessageEventArgs(UiMessageType messageType, string message, string title, UiMessageOptions options, TaskCompletionSource<bool> callback)
+    public UiMessageEventArgs(UiMessageType messageType, string message, string? title, UiMessageOptions options, TaskCompletionSource<bool> callback)
     {
         MessageType = messageType;
         Message = message;
@@ -26,7 +26,7 @@ public class UiMessageEventArgs : EventArgs
 
     public string Message { get; }
 
-    public string Title { get; }
+    public string? Title { get; }
 
     public UiMessageOptions Options { get; }
 
diff --git a/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Notifications/UiNotificationEventArgs.cs b/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Notifications/UiNotificationEventArgs.cs
index 554450d025..c12f7a0f06 100644
--- a/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Notifications/UiNotificationEventArgs.cs
+++ b/framework/src/Volo.Abp.AspNetCore.Components/Volo/Abp/AspNetCore/Components/Notifications/UiNotificationEventArgs.cs
@@ -4,7 +4,7 @@ namespace Volo.Abp.AspNetCore.Components.Notifications;
 
 public class UiNotificationEventArgs : EventArgs
 {
-    public UiNotificationEventArgs(UiNotificationType notificationType, string message, string title, UiNotificationOptions options)
+    public UiNotificationEventArgs(UiNotificationType notificationType, string message, string? title, UiNotificationOptions options)
     {
         NotificationType = notificationType;
         Message = message;
@@ -16,7 +16,7 @@ public class UiNotificationEventArgs : EventArgs
 
     public string Message { get; }
 
-    public string Title { get; }
+    public string? Title { get; }
 
     public UiNotificationOptions Options { get; }
 }
diff --git a/framework/src/Volo.Abp.AutoMapper/AutoMapper/AbpAutoMapperExtensibleDtoExtensions.cs b/framework/src/Volo.Abp.AutoMapper/AutoMapper/AbpAutoMapperExtensibleDtoExtensions.cs
index a564edf18f..f4697a443a 100644
--- a/framework/src/Volo.Abp.AutoMapper/AutoMapper/AbpAutoMapperExtensibleDtoExtensions.cs
+++ b/framework/src/Volo.Abp.AutoMapper/AutoMapper/AbpAutoMapperExtensibleDtoExtensions.cs
@@ -22,8 +22,8 @@ public static class AbpAutoMapperExtensibleDtoExtensions
                     (source, destination, extraProps) =>
                     {
                         var result = extraProps.IsNullOrEmpty()
-                            ? new Dictionary<string, object>()
-                            : new Dictionary<string, object>(extraProps);
+                            ? new Dictionary<string, object?>()
+                            : new Dictionary<string, object?>(extraProps);
 
                         ExtensibleObjectMapper
                             .MapExtraPropertiesTo<TSource, TDestination>(
diff --git a/framework/src/Volo.Abp.BlazoriseUI/AbpCrudPageBase.cs b/framework/src/Volo.Abp.BlazoriseUI/AbpCrudPageBase.cs
index f476ecad89..58867d6e5d 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/AbpCrudPageBase.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/AbpCrudPageBase.cs
@@ -174,32 +174,32 @@ public abstract class AbpCrudPageBase<
     where TCreateViewModel : class, new()
     where TUpdateViewModel : class, new()
 {
-    [Inject] protected TAppService AppService { get; set; }
-    [Inject] protected IStringLocalizer<AbpUiResource> UiLocalizer { get; set; }
-    [Inject] public IAbpEnumLocalizer AbpEnumLocalizer { get; set; }
+    [Inject] protected TAppService AppService { get; set; } = default!;
+    [Inject] protected IStringLocalizer<AbpUiResource> UiLocalizer { get; set; } = default!;
+    [Inject] public IAbpEnumLocalizer AbpEnumLocalizer { get; set; } = default!;
 
     protected virtual int PageSize { get; } = LimitedResultRequestDto.DefaultMaxResultCount;
 
     protected int CurrentPage = 1;
-    protected string CurrentSorting;
+    protected string CurrentSorting = default!;
     protected int? TotalCount;
     protected TGetListInput GetListInput = new TGetListInput();
     protected IReadOnlyList<TListViewModel> Entities = Array.Empty<TListViewModel>();
     protected TCreateViewModel NewEntity;
-    protected TKey EditingEntityId;
+    protected TKey EditingEntityId = default!;
     protected TUpdateViewModel EditingEntity;
-    protected Modal CreateModal;
-    protected Modal EditModal;
-    protected Validations CreateValidationsRef;
-    protected Validations EditValidationsRef;
+    protected Modal? CreateModal;
+    protected Modal? EditModal;
+    protected Validations? CreateValidationsRef;
+    protected Validations? EditValidationsRef;
     protected List<BreadcrumbItem> BreadcrumbItems = new List<BreadcrumbItem>(2);
-    protected DataGridEntityActionsColumn<TListViewModel> EntityActionsColumn;
+    protected DataGridEntityActionsColumn<TListViewModel> EntityActionsColumn = default!;
     protected EntityActionDictionary EntityActions { get; set; }
     protected TableColumnDictionary TableColumns { get; set; }
 
-    protected string CreatePolicyName { get; set; }
-    protected string UpdatePolicyName { get; set; }
-    protected string DeletePolicyName { get; set; }
+    protected string? CreatePolicyName { get; set; }
+    protected string? UpdatePolicyName { get; set; }
+    protected string? DeletePolicyName { get; set; }
 
     public bool HasCreatePermission { get; set; }
     public bool HasUpdatePermission { get; set; }
@@ -360,7 +360,7 @@ public abstract class AbpCrudPageBase<
     protected virtual Task CloseCreateModalAsync()
     {
         NewEntity = new TCreateViewModel();
-        return InvokeAsync(CreateModal.Hide);
+        return InvokeAsync(CreateModal!.Hide);
     }
 
     protected virtual Task ClosingCreateModal(ModalClosingEventArgs eventArgs)
@@ -429,7 +429,7 @@ public abstract class AbpCrudPageBase<
 
     protected virtual Task CloseEditModalAsync()
     {
-        InvokeAsync(EditModal.Hide);
+        InvokeAsync(EditModal!.Hide);
         return Task.CompletedTask;
     }
 
@@ -477,7 +477,7 @@ public abstract class AbpCrudPageBase<
         NewEntity = new TCreateViewModel();
         await GetEntitiesAsync();
 
-        await InvokeAsync(CreateModal.Hide);
+        await InvokeAsync(CreateModal!.Hide);
     }
 
     protected virtual async Task UpdateEntityAsync()
@@ -515,7 +515,7 @@ public abstract class AbpCrudPageBase<
     {
         await GetEntitiesAsync();
 
-        await InvokeAsync(EditModal.Hide);
+        await InvokeAsync(EditModal!.Hide);
     }
 
     protected virtual async Task DeleteEntityAsync(TListViewModel entity)
@@ -572,7 +572,7 @@ public abstract class AbpCrudPageBase<
     /// Does nothing if <paramref name="policyName"/> is null or empty.
     /// </summary>
     /// <param name="policyName">A policy name to check</param>
-    protected virtual async Task CheckPolicyAsync([CanBeNull] string policyName)
+    protected virtual async Task CheckPolicyAsync(string? policyName)
     {
         if (string.IsNullOrEmpty(policyName))
         {
@@ -633,7 +633,7 @@ public abstract class AbpCrudPageBase<
                 if (propertyInfo.Name.EndsWith("_Text"))
                 {
                     var lookupPropertyName = propertyInfo.Name.RemovePostFix("_Text");
-                    var lookupPropertyDefinition = properties.SingleOrDefault(t => t.Name == lookupPropertyName);
+                    var lookupPropertyDefinition = properties.SingleOrDefault(t => t.Name == lookupPropertyName)!;
                     yield return new TableColumn
                     {
                         Title = lookupPropertyDefinition.GetLocalizedDisplayName(StringLocalizerFactory),
@@ -658,7 +658,7 @@ public abstract class AbpCrudPageBase<
                     if (propertyInfo.Type.IsEnum)
                     {
                         column.ValueConverter = (val) =>
-                            AbpEnumLocalizer.GetString(propertyInfo.Type, val.As<ExtensibleObject>().ExtraProperties[propertyInfo.Name], new IStringLocalizer[]{ StringLocalizerFactory.CreateDefaultOrNull() });
+                            AbpEnumLocalizer.GetString(propertyInfo.Type, val.As<ExtensibleObject>().ExtraProperties[propertyInfo.Name]!, new IStringLocalizer?[]{ StringLocalizerFactory.CreateDefaultOrNull() });
                     }
 
                     yield return column;
diff --git a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiMessageService.cs b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiMessageService.cs
index de72bdaae2..6631a2236b 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiMessageService.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiMessageService.cs
@@ -15,7 +15,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
     /// <summary>
     /// An event raised after the message is received. Used to notify the message dialog.
     /// </summary>
-    public event EventHandler<UiMessageEventArgs> MessageReceived;
+    public event EventHandler<UiMessageEventArgs>? MessageReceived ;
 
     private readonly IStringLocalizer<AbpUiResource> localizer;
 
@@ -29,7 +29,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
         Logger = NullLogger<BlazoriseUiMessageService>.Instance;
     }
 
-    public Task Info(string message, string title = null, Action<UiMessageOptions> options = null)
+    public Task Info(string message, string? title = null, Action<UiMessageOptions>? options = null)
     {
         var uiMessageOptions = CreateDefaultOptions();
         options?.Invoke(uiMessageOptions);
@@ -39,7 +39,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
         return Task.CompletedTask;
     }
 
-    public Task Success(string message, string title = null, Action<UiMessageOptions> options = null)
+    public Task Success(string message, string? title = null, Action<UiMessageOptions>? options = null)
     {
         var uiMessageOptions = CreateDefaultOptions();
         options?.Invoke(uiMessageOptions);
@@ -49,7 +49,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
         return Task.CompletedTask;
     }
 
-    public Task Warn(string message, string title = null, Action<UiMessageOptions> options = null)
+    public Task Warn(string message, string? title = null, Action<UiMessageOptions>? options = null)
     {
         var uiMessageOptions = CreateDefaultOptions();
         options?.Invoke(uiMessageOptions);
@@ -59,7 +59,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
         return Task.CompletedTask;
     }
 
-    public Task Error(string message, string title = null, Action<UiMessageOptions> options = null)
+    public Task Error(string message, string? title = null, Action<UiMessageOptions>? options = null)
     {
         var uiMessageOptions = CreateDefaultOptions();
         options?.Invoke(uiMessageOptions);
@@ -69,7 +69,7 @@ public class BlazoriseUiMessageService : IUiMessageService, IScopedDependency
         return Task.CompletedTask;
     }
 
-    public Task<bool> Confirm(string message, string title = null, Action<UiMessageOptions> options = null)
+    public Task<bool> Confirm(string message, string? title = null, Action<UiMessageOptions>? options = null)
     {
         var uiMessageOptions = CreateDefaultOptions();
         options?.Invoke(uiMessageOptions);
diff --git a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiNotificationService.cs b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiNotificationService.cs
index cd993f7f46..f34e34b890 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiNotificationService.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiNotificationService.cs
@@ -11,9 +11,9 @@ public class BlazoriseUiNotificationService : IUiNotificationService, IScopedDep
     /// <summary>
     /// An event raised after the notification is received.
     /// </summary>
-    public event EventHandler<UiNotificationEventArgs> NotificationReceived;
+    public event EventHandler<UiNotificationEventArgs>? NotificationReceived;
 
-    public Task Info(string message, string title = null, Action<UiNotificationOptions> options = null)
+    public Task Info(string message, string? title = null, Action<UiNotificationOptions>? options = null)
     {
         var uiNotificationOptions = CreateDefaultOptions();
         options?.Invoke(uiNotificationOptions);
@@ -23,7 +23,7 @@ public class BlazoriseUiNotificationService : IUiNotificationService, IScopedDep
         return Task.CompletedTask;
     }
 
-    public Task Success(string message, string title = null, Action<UiNotificationOptions> options = null)
+    public Task Success(string message, string? title = null, Action<UiNotificationOptions>? options = null)
     {
         var uiNotificationOptions = CreateDefaultOptions();
         options?.Invoke(uiNotificationOptions);
@@ -33,7 +33,7 @@ public class BlazoriseUiNotificationService : IUiNotificationService, IScopedDep
         return Task.CompletedTask;
     }
 
-    public Task Warn(string message, string title = null, Action<UiNotificationOptions> options = null)
+    public Task Warn(string message, string? title = null, Action<UiNotificationOptions>? options = null)
     {
         var uiNotificationOptions = CreateDefaultOptions();
         options?.Invoke(uiNotificationOptions);
@@ -43,7 +43,7 @@ public class BlazoriseUiNotificationService : IUiNotificationService, IScopedDep
         return Task.CompletedTask;
     }
 
-    public Task Error(string message, string title = null, Action<UiNotificationOptions> options = null)
+    public Task Error(string message, string? title = null, Action<UiNotificationOptions>? options = null)
     {
         var uiNotificationOptions = CreateDefaultOptions();
         options?.Invoke(uiNotificationOptions);
diff --git a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiObjectExtensionPropertyInfoExtensions.cs b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiObjectExtensionPropertyInfoExtensions.cs
index a0516d8b4e..a3cd7372a6 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiObjectExtensionPropertyInfoExtensions.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiObjectExtensionPropertyInfoExtensions.cs
@@ -44,7 +44,7 @@ public static class BlazoriseUiObjectExtensionPropertyInfoExtensions
             typeof(PhoneAttribute)
         };
 
-    public static string GetDateEditInputFormatOrNull(this IBasicObjectExtensionPropertyInfo property)
+    public static string? GetDateEditInputFormatOrNull(this IBasicObjectExtensionPropertyInfo property)
     {
         if (property.IsDate())
         {
@@ -59,7 +59,7 @@ public static class BlazoriseUiObjectExtensionPropertyInfoExtensions
         return null;
     }
 
-    public static string GetTextInputValueOrNull(this IBasicObjectExtensionPropertyInfo property, object value)
+    public static string? GetTextInputValueOrNull(this IBasicObjectExtensionPropertyInfo property, object? value)
     {
         if (value == null)
         {
@@ -74,7 +74,7 @@ public static class BlazoriseUiObjectExtensionPropertyInfoExtensions
         return value.ToString();
     }
 
-    public static T GetInputValueOrDefault<T>(this IBasicObjectExtensionPropertyInfo property, object value)
+    public static T? GetInputValueOrDefault<T>(this IBasicObjectExtensionPropertyInfo property, object? value)
     {
         if (value == null)
         {
@@ -204,7 +204,7 @@ public static class BlazoriseUiObjectExtensionPropertyInfoExtensions
                ?? typeof(TextExtensionProperty<,>); //default
     }
 
-    private static Type GetInputTypeFromAttributeOrNull(Attribute attribute)
+    private static Type? GetInputTypeFromAttributeOrNull(Attribute attribute)
     {
         var hasTextEditSupport = TextEditSupportedAttributeTypes.Any(t => t == attribute.GetType());
 
@@ -238,7 +238,7 @@ public static class BlazoriseUiObjectExtensionPropertyInfoExtensions
         return null;
     }
 
-    private static Type GetInputTypeFromTypeOrNull(Type type)
+    private static Type? GetInputTypeFromTypeOrNull(Type type)
     {
         if (type == typeof(bool))
         {
diff --git a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiPageProgressService.cs b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiPageProgressService.cs
index d2d82ad8a5..a49fc8aecc 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiPageProgressService.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/BlazoriseUiPageProgressService.cs
@@ -12,9 +12,9 @@ public class BlazoriseUiPageProgressService : IUiPageProgressService,
     /// <summary>
     /// An event raised after the notification is received.
     /// </summary>
-    public event EventHandler<UiPageProgressEventArgs> ProgressChanged;
+    public event EventHandler<UiPageProgressEventArgs>? ProgressChanged;
 
-    public Task Go(int? percentage, Action<UiPageProgressOptions> options = null)
+    public Task Go(int? percentage, Action<UiPageProgressOptions>? options = null)
     {
         var uiPageProgressOptions = CreateDefaultOptions();
         options?.Invoke(uiPageProgressOptions);
diff --git a/framework/src/Volo.Abp.BlazoriseUI/BreadcrumbItem.cs b/framework/src/Volo.Abp.BlazoriseUI/BreadcrumbItem.cs
index 3ccb68698f..7f02b02b85 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/BreadcrumbItem.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/BreadcrumbItem.cs
@@ -6,11 +6,11 @@ public class BreadcrumbItem
 {
     public string Text { get; set; }
 
-    public object Icon { get; set; }
+    public object? Icon { get; set; }
 
-    public string Url { get; set; }
+    public string? Url { get; set; }
 
-    public BreadcrumbItem(string text, string url = null, object icon = null)
+    public BreadcrumbItem(string text, string? url = null, object? icon = null)
     {
         Text = text;
         Url = url;
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor b/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor
index cbdfc25c99..522140811e 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor
@@ -121,7 +121,7 @@
                                     @{
                                         var entity = context as IHasExtraProperties;
                                         var propertyName = ExtensionPropertiesRegex.Match(column.Data).Groups[1].Value;
-                                        var propertyValue = entity.GetProperty(propertyName);
+                                        var propertyValue = entity?.GetProperty(propertyName);
                                         if (propertyValue != null && propertyValue.GetType() == typeof(bool))
                                         {
                                             if ((bool) propertyValue)
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor.cs
index f9baf631f5..4642afcadd 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/AbpExtensibleDataGrid.razor.cs
@@ -18,7 +18,7 @@ public partial class AbpExtensibleDataGrid<TItem> : ComponentBase
 
     protected Regex ExtensionPropertiesRegex = new Regex(@"ExtraProperties\[(.*?)\]");
 
-    [Parameter] public IEnumerable<TItem> Data { get; set; }
+    [Parameter] public IEnumerable<TItem> Data { get; set; } = default!;
 
     [Parameter] public EventCallback<DataGridReadDataEventArgs<TItem>> ReadData { get; set; }
 
@@ -28,16 +28,16 @@ public partial class AbpExtensibleDataGrid<TItem> : ComponentBase
 
     [Parameter] public int PageSize { get; set; }
 
-    [Parameter] public IEnumerable<TableColumn> Columns { get; set; }
+    [Parameter] public IEnumerable<TableColumn> Columns { get; set; } = default!;
 
     [Parameter] public int CurrentPage { get; set; } = 1;
 
-    [Parameter] public string Class { get; set; }
+    [Parameter] public string? Class { get; set; }
 
     [Parameter] public bool Responsive { get; set; }
 
     [Inject]
-    public IStringLocalizerFactory StringLocalizerFactory { get; set; }
+    public IStringLocalizerFactory StringLocalizerFactory { get; set; } = default!;
 
     protected virtual RenderFragment RenderCustomTableColumnComponent(Type type, object data)
     {
@@ -51,10 +51,10 @@ public partial class AbpExtensibleDataGrid<TItem> : ComponentBase
 
     protected virtual string GetConvertedFieldValue(TItem item, TableColumn columnDefinition)
     {
-        var convertedValue = columnDefinition.ValueConverter.Invoke(item);
+        var convertedValue = columnDefinition.ValueConverter!.Invoke(item!);
         if (!columnDefinition.DisplayFormat.IsNullOrEmpty())
         {
-            return string.Format(columnDefinition.DisplayFormatProvider, columnDefinition.DisplayFormat,
+            return string.Format(columnDefinition.DisplayFormatProvider, columnDefinition.DisplayFormat!,
                 convertedValue);
         }
 
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/AlertWrapper.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/AlertWrapper.cs
index ba2024cecb..04b9f18a48 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/AlertWrapper.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/AlertWrapper.cs
@@ -4,6 +4,6 @@ namespace Volo.Abp.BlazoriseUI.Components;
 
 internal class AlertWrapper
 {
-    public AlertMessage AlertMessage { get; set; }
+    public AlertMessage AlertMessage { get; set; } = default!;
     public bool IsVisible { get; set; }
 }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/DataGridEntityActionsColumn.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/DataGridEntityActionsColumn.razor.cs
index 3d52012efd..9a39acd4fc 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/DataGridEntityActionsColumn.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/DataGridEntityActionsColumn.razor.cs
@@ -10,7 +10,7 @@ namespace Volo.Abp.BlazoriseUI.Components;
 public partial class DataGridEntityActionsColumn<TItem> : DataGridColumn<TItem>
 {
     [Inject]
-    public IStringLocalizer<AbpUiResource> UiLocalizer { get; set; }
+    public IStringLocalizer<AbpUiResource> UiLocalizer { get; set; } = default!;
 
     protected override async Task OnInitializedAsync()
     {
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityAction.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityAction.razor.cs
index a38d915ff1..ef487bafcb 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityAction.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityAction.razor.cs
@@ -18,7 +18,7 @@ public partial class EntityAction<TItem> : ComponentBase
     internal bool HasPermission { get; set; } = true;
 
     [Parameter]
-    public string Text { get; set; }
+    public string Text { get; set; } = default!;
 
     [Parameter]
     public bool Primary { get; set; }
@@ -28,25 +28,25 @@ public partial class EntityAction<TItem> : ComponentBase
 
     [Parameter]
     [Obsolete("Use Visible to hide actions based on permissions. Check the permission yourself. It is more performant. This option might be removed in future versions.")]
-    public string RequiredPolicy { get; set; }
+    public string? RequiredPolicy { get; set; }
 
     [Parameter]
-    public Color Color { get; set; }
+    public Color? Color { get; set; }
 
     [Parameter]
-    public Func<string> ConfirmationMessage { get; set; }
+    public Func<string>? ConfirmationMessage { get; set; }
 
     [Parameter]
-    public string Icon { get; set; }
+    public string? Icon { get; set; }
 
     [CascadingParameter]
-    public EntityActions<TItem> ParentActions { get; set; }
+    public EntityActions<TItem> ParentActions { get; set; } = default!;
 
     [Inject]
-    protected IAuthorizationService AuthorizationService { get; set; }
+    protected IAuthorizationService AuthorizationService { get; set; } = default!;
 
     [Inject]
-    protected IUiMessageService UiMessageService { get; set; }
+    protected IUiMessageService UiMessageService { get; set; } = default!;
 
     protected async override Task OnInitializedAsync()
     {
@@ -55,7 +55,7 @@ public partial class EntityAction<TItem> : ComponentBase
 
         if (!RequiredPolicy.IsNullOrEmpty())
         {
-            HasPermission = await AuthorizationService.IsGrantedAsync(RequiredPolicy);
+            HasPermission = await AuthorizationService.IsGrantedAsync(RequiredPolicy!);
         }
         ParentActions.AddAction(this);
     }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor
index b362358d70..844dea4950 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor
@@ -6,7 +6,7 @@
             @if ( HasPrimaryAction )
             {
                 <Button Block="true"
-                        Color="@PrimaryAction.Color"
+                        Color="@PrimaryAction!.Color"
                         Clicked="async ()=> await PrimaryAction.ActionClickedAsync()"
                         Disabled=@PrimaryAction.Disabled>
                     @PrimaryAction.Text
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor.cs
index 4ba27bf2f7..8a007c1046 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/EntityActions.razor.cs
@@ -12,19 +12,19 @@ public partial class EntityActions<TItem> : ComponentBase
 {
     protected readonly List<EntityAction<TItem>> Actions = new List<EntityAction<TItem>>();
     protected bool HasPrimaryAction => Actions.Any(t => t.Primary);
-    protected EntityAction<TItem> PrimaryAction => Actions.FirstOrDefault(t => t.Primary);
+    protected EntityAction<TItem>? PrimaryAction => Actions.FirstOrDefault(t => t.Primary);
 
     [Parameter]
     public Color ToggleColor { get; set; } = Color.Primary;
 
     [Parameter]
-    public string ToggleText { get; set; }
+    public string? ToggleText { get; set; }
 
     [Parameter]
-    public RenderFragment ChildContent { get; set; }
+    public RenderFragment ChildContent { get; set; } = default!;
 
     [Parameter]
-    public DataGridEntityActionsColumn<TItem> EntityActionsColumn { get; set; }
+    public DataGridEntityActionsColumn<TItem> EntityActionsColumn { get; set; } = default!;
 
     [Parameter]
     public ActionType Type { get; set; } = ActionType.Dropdown;
@@ -33,10 +33,10 @@ public partial class EntityActions<TItem> : ComponentBase
     public bool Disabled { get; set; } = false;
 
     [CascadingParameter]
-    public DataGridEntityActionsColumn<TItem> ParentEntityActionsColumn { get; set; }
+    public DataGridEntityActionsColumn<TItem>? ParentEntityActionsColumn { get; set; }
 
     [Inject]
-    public IStringLocalizer<AbpUiResource> UiLocalizer { get; set; }
+    public IStringLocalizer<AbpUiResource> UiLocalizer { get; set; } = default!;
 
     internal void AddAction(EntityAction<TItem> action)
     {
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/EnumHelper.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/EnumHelper.cs
index 925476ae77..b1858da261 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/EnumHelper.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/EnumHelper.cs
@@ -17,17 +17,17 @@ public static class EnumHelper
         var localizedMemberName = AbpInternalLocalizationHelper.LocalizeWithFallback(
             new[]
             {
-                        stringLocalizerFactory.CreateDefaultOrNull()
+                stringLocalizerFactory.CreateDefaultOrNull()
             },
             new[]
             {
-                        $"Enum:{enumType.Name}.{value}",
-                        $"Enum:{enumType.Name}.{memberName}",
-                        $"{enumType.Name}.{value}",
-                        $"{enumType.Name}.{memberName}",
-                        memberName
-            },
-            memberName
+                $"Enum:{enumType.Name}.{value}",
+                $"Enum:{enumType.Name}.{memberName}",
+                $"{enumType.Name}.{value}",
+                $"{enumType.Name}.{memberName}",
+                memberName
+            }!,
+            memberName!
         );
 
         return localizedMemberName;
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionProperties.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionProperties.razor.cs
index d9a1a42d85..beba718f0b 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionProperties.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionProperties.razor.cs
@@ -10,13 +10,13 @@ public partial class ExtensionProperties<TEntityType, TResourceType> : Component
     where TEntityType : IHasExtraProperties
 {
     [Inject]
-    public IStringLocalizerFactory StringLocalizerFactory { get; set; }
+    public IStringLocalizerFactory StringLocalizerFactory { get; set; } = default!;
 
     [Parameter]
-    public AbpBlazorMessageLocalizerHelper<TResourceType> LH { get; set; }
+    public AbpBlazorMessageLocalizerHelper<TResourceType> LH { get; set; } = default!;
 
     [Parameter]
-    public TEntityType Entity { get; set; }
+    public TEntityType Entity { get; set; } = default!;
     
     [Parameter]
     public ExtensionPropertyModalType? ModalType { get; set; }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionPropertyComponentBase.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionPropertyComponentBase.cs
index 46f4bd7f51..ec09d57c9a 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionPropertyComponentBase.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/ExtensionPropertyComponentBase.cs
@@ -16,22 +16,22 @@ public abstract class ExtensionPropertyComponentBase<TEntity, TResourceType> : O
     where TEntity : IHasExtraProperties
 {
     [Inject]
-    public IStringLocalizerFactory StringLocalizerFactory { get; set; }
+    public IStringLocalizerFactory StringLocalizerFactory { get; set; } = default!;
 
     [Inject]
-    public IAbpEnumLocalizer AbpEnumLocalizer { get; set; }
+    public IAbpEnumLocalizer AbpEnumLocalizer { get; set; } = default!;
 
     [Inject]
-    public IValidationMessageLocalizerAttributeFinder ValidationMessageLocalizerAttributeFinder { get; set; }
+    public IValidationMessageLocalizerAttributeFinder ValidationMessageLocalizerAttributeFinder { get; set; } = default!;
 
     [Parameter]
-    public TEntity Entity { get; set; }
+    public TEntity Entity { get; set; } = default!;
 
     [Parameter]
-    public ObjectExtensionPropertyInfo PropertyInfo { get; set; }
+    public ObjectExtensionPropertyInfo PropertyInfo { get; set; } = default!;
 
     [Parameter]
-    public AbpBlazorMessageLocalizerHelper<TResourceType> LH { get; set; }
+    public AbpBlazorMessageLocalizerHelper<TResourceType> LH { get; set; } = default!;
 
     [Parameter]
     public ExtensionPropertyModalType? ModalType { get; set; }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/LookupExtensionProperty.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/LookupExtensionProperty.razor.cs
index 5da0138d9d..dcb301c3b7 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/LookupExtensionProperty.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/LookupExtensionProperty.razor.cs
@@ -25,11 +25,11 @@ public partial class LookupExtensionProperty<TEntity, TResourceType>
 {
     protected List<SelectItem<object>> lookupItems = new();
 
-    [Inject] public ILookupApiRequestService LookupApiService { get; set; }
+    [Inject] public ILookupApiRequestService LookupApiService { get; set; } = default!;
 
     public string TextPropertyName => PropertyInfo.Name + "_Text";
 
-    public object SelectedValue {
+    public object? SelectedValue {
         get { return Entity.GetProperty(PropertyInfo.Name); }
         set {
             Entity.SetProperty(PropertyInfo.Name, value, false);
@@ -45,7 +45,7 @@ public partial class LookupExtensionProperty<TEntity, TResourceType>
         {
             lookupItems.Add(new SelectItem<object>
             {
-                Text = Entity.GetProperty(TextPropertyName).ToString(),
+                Text = Entity.GetProperty(TextPropertyName)!.ToString()!,
                 Value = value
             });
         }
@@ -61,7 +61,7 @@ public partial class LookupExtensionProperty<TEntity, TResourceType>
         }
     }
 
-    protected virtual void UpdateLookupTextProperty(object value)
+    protected virtual void UpdateLookupTextProperty(object? value)
     {
         var selectedItemText = lookupItems.SingleOrDefault(t => t.Value.Equals(value))?.Text;
         Entity.SetProperty(TextPropertyName, selectedItemText);
@@ -85,8 +85,8 @@ public partial class LookupExtensionProperty<TEntity, TResourceType>
         {
             selectItems.Add(new SelectItem<object>
             {
-                Text = item.GetProperty(PropertyInfo.Lookup.DisplayPropertyName).GetString(),
-                Value = JsonSerializer.Deserialize(item.GetProperty(PropertyInfo.Lookup.ValuePropertyName).GetRawText(), PropertyInfo.Type)
+                Text = item.GetProperty(PropertyInfo.Lookup.DisplayPropertyName).GetString()!,
+                Value = JsonSerializer.Deserialize(item.GetProperty(PropertyInfo.Lookup.ValuePropertyName).GetRawText(), PropertyInfo.Type)!
             });
         }
 
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/SelectExtensionProperty.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/SelectExtensionProperty.razor.cs
index 32bb53c0fa..d7ec33be91 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/SelectExtensionProperty.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/SelectExtensionProperty.razor.cs
@@ -44,13 +44,13 @@ public partial class SelectExtensionProperty<TEntity, TResourceType>
 
         if (!Entity.HasProperty(PropertyInfo.Name))
         {
-            SelectedValue = (int)PropertyInfo.Type.GetEnumValues().GetValue(0);
+            SelectedValue = (int)PropertyInfo.Type.GetEnumValues().GetValue(0)!;
         }
     }
 }
 
 public class SelectItem<TValue>
 {
-    public string Text { get; set; }
-    public TValue Value { get; set; }
+    public string Text { get; set; } = default!;
+    public TValue Value { get; set; } = default!;
 }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/TextExtensionProperty.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/TextExtensionProperty.razor.cs
index 6fe9c9fb71..67a1928453 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/TextExtensionProperty.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ObjectExtending/TextExtensionProperty.razor.cs
@@ -5,7 +5,7 @@ namespace Volo.Abp.BlazoriseUI.Components.ObjectExtending;
 public partial class TextExtensionProperty<TEntity, TResourceType>
     where TEntity : IHasExtraProperties
 {
-    protected string Value {
+    protected string? Value {
         get {
             return PropertyInfo.GetTextInputValueOrNull(Entity.GetProperty(PropertyInfo.Name));
         }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/PageAlert.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/PageAlert.razor.cs
index 33d4730abf..c99020d8bd 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/PageAlert.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/PageAlert.razor.cs
@@ -14,10 +14,10 @@ public partial class PageAlert : ComponentBase, IDisposable
     private List<AlertWrapper> Alerts = new List<AlertWrapper>();
 
     [Inject]
-    protected IAlertManager AlertManager { get; set; }
+    protected IAlertManager AlertManager { get; set; } = default!;
 
     [Inject]
-    protected NavigationManager NavigationManager { get; set; }
+    protected NavigationManager NavigationManager { get; set; } = default!;
 
     protected override void OnInitialized()
     {
@@ -33,17 +33,17 @@ public partial class PageAlert : ComponentBase, IDisposable
     }
 
     //Since Blazor WASM doesn't support scoped dependency, we need to clear alerts on each location changed event.
-    private void NavigationManager_LocationChanged(object sender, LocationChangedEventArgs e)
+    private void NavigationManager_LocationChanged(object? sender, LocationChangedEventArgs e)
     {
         AlertManager.Alerts.Clear();
         Alerts.Clear();
     }
 
-    private void Alerts_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
+    private void Alerts_CollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
     {
         if (e.Action == NotifyCollectionChangedAction.Add)
         {
-            foreach (var item in e.NewItems)
+            foreach (var item in e.NewItems!)
             {
                 Alerts.Add(new AlertWrapper
                 {
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/SubmitButton.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/SubmitButton.razor.cs
index a9a19d3685..0afb0dfe5b 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/SubmitButton.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/SubmitButton.razor.cs
@@ -12,7 +12,7 @@ public partial class SubmitButton : ComponentBase
     protected bool Submiting { get; set; }
 
     [Parameter]
-    public string Form { get; set; }
+    public string Form { get; set; } = default!;
 
     [Parameter]
     public ButtonType Type { get; set; } = ButtonType.Submit;
@@ -36,10 +36,10 @@ public partial class SubmitButton : ComponentBase
     public EventCallback Clicked { get; set; }
 
     [Parameter]
-    public RenderFragment ChildContent { get; set; }
+    public RenderFragment? ChildContent { get; set; }
 
     [Inject]
-    protected IStringLocalizer<AbpUiResource> StringLocalizer { get; set; }
+    protected IStringLocalizer<AbpUiResource> StringLocalizer { get; set; } = default!;
 
     protected bool IsDisabled
         => Disabled == true || Submiting;
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/ToolbarButton.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/ToolbarButton.razor.cs
index 146d205013..9c4f5bc0c4 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/ToolbarButton.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/ToolbarButton.razor.cs
@@ -8,16 +8,16 @@ namespace Volo.Abp.BlazoriseUI.Components;
 public partial class ToolbarButton : ComponentBase
 {
     [Parameter]
-    public Color Color { get; set; }
+    public Color? Color { get; set; }
 
     [Parameter]
-    public object Icon { get; set; }
+    public object? Icon { get; set; }
 
     [Parameter]
-    public string Text { get; set; }
+    public string Text { get; set; } = default!;
 
     [Parameter]
-    public Func<Task> Clicked { get; set; }
+    public Func<Task> Clicked { get; set; } = default!;
 
     [Parameter]
     public bool Disabled { get; set; }
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/UiMessageAlert.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/UiMessageAlert.razor.cs
index c7fe013b3c..60ba8e8dd7 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/UiMessageAlert.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/UiMessageAlert.razor.cs
@@ -10,7 +10,7 @@ namespace Volo.Abp.BlazoriseUI.Components;
 
 public partial class UiMessageAlert : ComponentBase, IDisposable
 {
-    protected Modal ModalRef { get; set; }
+    protected Modal ModalRef { get; set; } = default!;
 
     protected virtual bool IsConfirmation
         => MessageType == UiMessageType.Confirmation;
@@ -21,7 +21,7 @@ public partial class UiMessageAlert : ComponentBase, IDisposable
     protected virtual bool ShowMessageIcon
        => Options?.ShowMessageIcon ?? true;
 
-    protected virtual object MessageIcon => Options?.MessageIcon ?? MessageType switch
+    protected virtual object? MessageIcon => Options?.MessageIcon ?? MessageType switch
     {
         UiMessageType.Info => IconName.Info,
         UiMessageType.Success => IconName.Check,
@@ -31,7 +31,7 @@ public partial class UiMessageAlert : ComponentBase, IDisposable
         _ => null,
     };
 
-    protected virtual string MessageIconColor => MessageType switch
+    protected virtual string? MessageIconColor => MessageType switch
     {
         // gets the color in the order of importance: Blazorise > Bootstrap > fallback color
         UiMessageType.Info => "var(--b-theme-info, var(--info, #17a2b8))",
@@ -63,13 +63,13 @@ public partial class UiMessageAlert : ComponentBase, IDisposable
 
     [Parameter] public UiMessageType MessageType { get; set; }
 
-    [Parameter] public string Title { get; set; }
+    [Parameter] public string? Title { get; set; }
 
-    [Parameter] public string Message { get; set; }
+    [Parameter] public string Message { get; set; } = default!;
 
-    [Parameter] public TaskCompletionSource<bool> Callback { get; set; }
+    [Parameter] public TaskCompletionSource<bool>? Callback { get; set; }
 
-    [Parameter] public UiMessageOptions Options { get; set; }
+    [Parameter] public UiMessageOptions? Options { get; set; }
 
     [Parameter] public EventCallback Okayed { get; set; }
 
@@ -77,16 +77,19 @@ public partial class UiMessageAlert : ComponentBase, IDisposable
 
     [Parameter] public EventCallback Canceled { get; set; }
 
-    [Inject] protected BlazoriseUiMessageService UiMessageService { get; set; }
+    [Inject] protected BlazoriseUiMessageService? UiMessageService { get; set; }
 
     protected override void OnInitialized()
     {
         base.OnInitialized();
 
-        UiMessageService.MessageReceived += OnMessageReceived;
+        if (UiMessageService != null)
+        {
+            UiMessageService.MessageReceived += OnMessageReceived;
+        }
     }
 
-    private async void OnMessageReceived(object sender, UiMessageEventArgs e)
+    private async void OnMessageReceived(object? sender, UiMessageEventArgs e)
     {
         MessageType = e.MessageType;
         Message = e.Message;
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/UiNotificationAlert.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/UiNotificationAlert.razor.cs
index 359ea1a422..4aebaf1f68 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/UiNotificationAlert.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/UiNotificationAlert.razor.cs
@@ -11,23 +11,23 @@ namespace Volo.Abp.BlazoriseUI.Components;
 
 public partial class UiNotificationAlert : ComponentBase, IDisposable
 {
-    protected SnackbarStack SnackbarStack { get; set; }
+    protected SnackbarStack SnackbarStack { get; set; } = default!;
 
     [Parameter] public UiNotificationType NotificationType { get; set; }
 
-    [Parameter] public string Message { get; set; }
+    [Parameter] public string Message { get; set; } = default!;
 
-    [Parameter] public string Title { get; set; }
+    [Parameter] public string? Title { get; set; }
 
-    [Parameter] public UiNotificationOptions Options { get; set; }
+    [Parameter] public UiNotificationOptions? Options { get; set; }
 
     [Parameter] public EventCallback Okayed { get; set; }
 
     [Parameter] public EventCallback Closed { get; set; }
 
-    [Inject] protected BlazoriseUiNotificationService UiNotificationService { get; set; }
+    [Inject] protected BlazoriseUiNotificationService? UiNotificationService { get; set; }
 
-    [Inject] protected IStringLocalizerFactory StringLocalizerFactory { get; set; }
+    [Inject] protected IStringLocalizerFactory StringLocalizerFactory { get; set; } = default!;
 
     protected virtual SnackbarColor GetSnackbarColor(UiNotificationType notificationType)
     {
@@ -45,10 +45,13 @@ public partial class UiNotificationAlert : ComponentBase, IDisposable
     {
         base.OnInitialized();
 
-        UiNotificationService.NotificationReceived += OnNotificationReceived;
+        if (UiNotificationService != null)
+        {
+            UiNotificationService.NotificationReceived += OnNotificationReceived;
+        }
     }
 
-    protected virtual async void OnNotificationReceived(object sender, UiNotificationEventArgs e)
+    protected virtual async void OnNotificationReceived(object? sender, UiNotificationEventArgs e)
     {
         NotificationType = e.NotificationType;
         Message = e.Message;
@@ -62,7 +65,7 @@ public partial class UiNotificationAlert : ComponentBase, IDisposable
         await SnackbarStack.PushAsync(Message, Title, GetSnackbarColor(e.NotificationType), (options) =>
         {
             options.CloseButtonIcon = IconName.Times;
-            options.ActionButtonText = okButtonText;
+            options.ActionButtonText = okButtonText!;
         });
     }
 
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Components/UiPageProgress.razor.cs b/framework/src/Volo.Abp.BlazoriseUI/Components/UiPageProgress.razor.cs
index f313591042..8e494cba2f 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Components/UiPageProgress.razor.cs
+++ b/framework/src/Volo.Abp.BlazoriseUI/Components/UiPageProgress.razor.cs
@@ -7,24 +7,27 @@ namespace Volo.Abp.BlazoriseUI.Components;
 
 public partial class UiPageProgress : ComponentBase, IDisposable
 {
-    protected PageProgress PageProgressRef { get; set; }
+    protected PageProgress PageProgressRef { get; set; } = default!;
 
     protected int? Percentage { get; set; }
 
     protected bool Visible { get; set; }
 
-    protected Color Color { get; set; }
+    protected Color Color { get; set; } = default!;
 
-    [Inject] protected IUiPageProgressService UiPageProgressService { get; set; }
+    [Inject] protected IUiPageProgressService? UiPageProgressService { get; set; }
 
     protected override void OnInitialized()
     {
         base.OnInitialized();
 
-        UiPageProgressService.ProgressChanged += OnProgressChanged;
+        if (UiPageProgressService != null)
+        {
+            UiPageProgressService.ProgressChanged += OnProgressChanged;
+        }
     }
 
-    private async void OnProgressChanged(object sender, UiPageProgressEventArgs e)
+    private async void OnProgressChanged(object? sender, UiPageProgressEventArgs e)
     {
         Percentage = e.Percentage;
         Visible = e.Percentage == null || (e.Percentage >= 0 && e.Percentage <= 100);
diff --git a/framework/src/Volo.Abp.BlazoriseUI/Volo.Abp.BlazoriseUI.csproj b/framework/src/Volo.Abp.BlazoriseUI/Volo.Abp.BlazoriseUI.csproj
index 5fa169715c..4fb1769daf 100644
--- a/framework/src/Volo.Abp.BlazoriseUI/Volo.Abp.BlazoriseUI.csproj
+++ b/framework/src/Volo.Abp.BlazoriseUI/Volo.Abp.BlazoriseUI.csproj
@@ -5,6 +5,8 @@
 
   <PropertyGroup>
     <TargetFramework>net7.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>Nullable</WarningsAsErrors>
   </PropertyGroup>
 
     <ItemGroup>
diff --git a/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/AbpInternalLocalizationHelper.cs b/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/AbpInternalLocalizationHelper.cs
index f697ba1344..32160b5cca 100644
--- a/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/AbpInternalLocalizationHelper.cs
+++ b/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/AbpInternalLocalizationHelper.cs
@@ -25,7 +25,7 @@ public static class AbpInternalLocalizationHelper
     /// <returns></returns>
     [Obsolete("Use IAbpEnumLocalizer instead.")]
     public static string LocalizeWithFallback(
-        IStringLocalizer[] localizers,
+        IStringLocalizer?[] localizers,
         string[] keys,
         string defaultValue)
     {
diff --git a/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/IAbpEnumLocalizer.cs b/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/IAbpEnumLocalizer.cs
index cb88667e1c..3ce72ae515 100644
--- a/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/IAbpEnumLocalizer.cs
+++ b/framework/src/Volo.Abp.Localization/Volo/Abp/Localization/IAbpEnumLocalizer.cs
@@ -7,5 +7,5 @@ public interface IAbpEnumLocalizer
 {
     string GetString(Type enumType, object enumValue);
 
-    string GetString(Type enumType, object enumValue, IStringLocalizer[] specifyLocalizers);
+    string GetString(Type enumType, object enumValue, IStringLocalizer?[] specifyLocalizers);
 }
diff --git a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionary.cs b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionary.cs
index c92014e9ea..b61323c7f6 100644
--- a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionary.cs
+++ b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionary.cs
@@ -4,14 +4,14 @@ using System.Collections.Generic;
 namespace Volo.Abp.Data;
 
 [Serializable]
-public class ExtraPropertyDictionary : Dictionary<string, object>
+public class ExtraPropertyDictionary : Dictionary<string, object?>
 {
     public ExtraPropertyDictionary()
     {
 
     }
 
-    public ExtraPropertyDictionary(IDictionary<string, object> dictionary)
+    public ExtraPropertyDictionary(IDictionary<string, object?> dictionary)
         : base(dictionary)
     {
     }
diff --git a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionaryExtensions.cs b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionaryExtensions.cs
index 6c4cd02d1b..518246dae2 100644
--- a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionaryExtensions.cs
+++ b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/ExtraPropertyDictionaryExtensions.cs
@@ -8,24 +8,24 @@ public static class ExtraPropertyDictionaryExtensions
     public static T ToEnum<T>(this ExtraPropertyDictionary extraPropertyDictionary, string key)
         where T : Enum
     {
-        if (extraPropertyDictionary[key].GetType() == typeof(T))
+        if (extraPropertyDictionary[key]!.GetType() == typeof(T))
         {
-            return (T)extraPropertyDictionary[key];
+            return (T)extraPropertyDictionary[key]!;
         }
 
-        extraPropertyDictionary[key] = Enum.Parse(typeof(T), extraPropertyDictionary[key].ToString()!, ignoreCase: true);
-        return (T)extraPropertyDictionary[key];
+        extraPropertyDictionary[key] = Enum.Parse(typeof(T), extraPropertyDictionary[key]!.ToString()!, ignoreCase: true);
+        return (T)extraPropertyDictionary[key]!;
     }
 
     public static object ToEnum(this ExtraPropertyDictionary extraPropertyDictionary, string key, Type enumType)
     {
-        if (!enumType.IsEnum || extraPropertyDictionary[key].GetType() == enumType)
+        if (!enumType.IsEnum || extraPropertyDictionary[key]!.GetType() == enumType)
         {
-            return extraPropertyDictionary[key];
+            return extraPropertyDictionary[key]!;
         }
 
-        extraPropertyDictionary[key] = Enum.Parse(enumType, extraPropertyDictionary[key].ToString()!, ignoreCase: true);
-        return extraPropertyDictionary[key];
+        extraPropertyDictionary[key] = Enum.Parse(enumType, extraPropertyDictionary[key]!.ToString()!, ignoreCase: true);
+        return extraPropertyDictionary[key]!;
     }
 
     public static bool HasSameItems(
diff --git a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/HasExtraPropertiesExtensions.cs b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/HasExtraPropertiesExtensions.cs
index 7423052772..ede0c65861 100644
--- a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/HasExtraPropertiesExtensions.cs
+++ b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/Data/HasExtraPropertiesExtensions.cs
@@ -20,7 +20,7 @@ public static class HasExtraPropertiesExtensions
 
     public static object? GetProperty(this IHasExtraProperties source, string name, object? defaultValue = null)
     {
-        return source.ExtraProperties?.GetOrDefault(name)
+        return source.ExtraProperties.GetOrDefault(name)
                ?? defaultValue;
     }
 
@@ -59,7 +59,7 @@ public static class HasExtraPropertiesExtensions
     public static TSource SetProperty<TSource>(
         this TSource source,
         string name,
-        object value,
+        object? value,
         bool validate = true)
         where TSource : IHasExtraProperties
     {
@@ -98,7 +98,7 @@ public static class HasExtraPropertiesExtensions
                 continue;
             }
 
-            source.ExtraProperties[property.Name] = property.GetDefaultValue()!;
+            source.ExtraProperties[property.Name] = property.GetDefaultValue();
         }
 
         return source;
diff --git a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ExtensibleObjectMapper.cs b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ExtensibleObjectMapper.cs
index fbf277c55b..eae85f77d7 100644
--- a/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ExtensibleObjectMapper.cs
+++ b/framework/src/Volo.Abp.ObjectExtending/Volo/Abp/ObjectExtending/ExtensibleObjectMapper.cs
@@ -75,8 +75,8 @@ public static class ExtensibleObjectMapper
     /// </param>
     /// <param name="ignoredProperties">Used to ignore some properties</param>
     public static void MapExtraPropertiesTo<TSource, TDestination>(
-        [NotNull] Dictionary<string, object> sourceDictionary,
-        [NotNull] Dictionary<string, object> destinationDictionary,
+        [NotNull] Dictionary<string, object?> sourceDictionary,
+        [NotNull] Dictionary<string, object?> destinationDictionary,
         MappingPropertyDefinitionChecks? definitionChecks = null,
         string[]? ignoredProperties = null)
         where TSource : IHasExtraProperties
@@ -110,8 +110,8 @@ public static class ExtensibleObjectMapper
     public static void MapExtraPropertiesTo(
         [NotNull] Type sourceType,
         [NotNull] Type destinationType,
-        [NotNull] Dictionary<string, object> sourceDictionary,
-        [NotNull] Dictionary<string, object> destinationDictionary,
+        [NotNull] Dictionary<string, object?> sourceDictionary,
+        [NotNull] Dictionary<string, object?> destinationDictionary,
         MappingPropertyDefinitionChecks? definitionChecks = null,
         string[]? ignoredProperties = null)
     {