Fixed an exception while writing some paths on the address bar (#6077)

Author: BanCrash

Files/Filesystem/StorageFileHelpers/StorageFileExtensions.cs

@@ -217,6 +217,11 @@ public async static Task<IList<StorageFileWithPath>> GetFilesWithPathAsync(this
 
         public async static Task<IList<StorageFolderWithPath>> GetFoldersWithPathAsync(this StorageFolderWithPath parentFolder, string nameFilter, uint maxNumberOfItems = uint.MaxValue)
         {
+            if (parentFolder == null)
+            {
+                return null;
+            }
+
             var queryOptions = new QueryOptions();
             queryOptions.ApplicationSearchFilter = $"System.FileName:{nameFilter}*";
             BaseStorageFolderQueryResult queryResult = parentFolder.Folder.CreateFolderQueryWithOptions(queryOptions);

Files/ViewModels/NavToolbarViewModel.cs

@@ -275,7 +275,11 @@ public bool IsSearchBoxVisible
         public string PathText
         {
             get => pathText;
-            set => SetProperty(ref pathText, value);
+            set
+            {
+                pathText = value;
+                OnPropertyChanged(nameof(PathText));
+            }
         }
 
         public ObservableCollection<ListedItem> NavigationBarSuggestions = new ObservableCollection<ListedItem>();
@@ -488,9 +492,11 @@ public bool IsEditModeEnabled
                 {
                     EditModeEnabled?.Invoke(this, new EventArgs());
 
-                    var visiblePath = NavToolbar.FindDescendant("VisiblePath") as Control;
+                    var visiblePath = NavToolbar.FindDescendant<AutoSuggestBox>(x => x.Name == "VisiblePath");
                     visiblePath?.Focus(FocusState.Programmatic);
                     visiblePath?.FindDescendant<TextBox>()?.SelectAll();
+
+                    AddressBarTextEntered?.Invoke(this, new AddressBarTextEnteredEventArgs() { AddressBarTextField = visiblePath });
                 }
                 else
                 {

Files/ViewModels/Previews/BasePreviewModel.cs

@@ -150,7 +150,7 @@ public static async Task<string> ReadFileAsText(BaseStorageFile file, int maxLen
                 {
                     var buffer = new byte[maxLength];
                     bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length);
-                    result.Append(Encoding.UTF8.GetString(buffer));
+                    result.Append(Encoding.UTF8.GetString(buffer, 0, bytesRead));
                 } while (bytesRead > 0 && result.Length <= maxLength);
                 return result.ToString();
             }