App layout

DotNetSolutionTools.App/Services/FileService.cs

@@ -0,0 +1,40 @@
+using Avalonia;
+using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Platform.Storage;
+
+namespace DotNetSolutionTools.App.Services;
+
+public class FileService
+{
+    public async Task<IStorageFile?> DoOpenFilePickerAsync()
+    {
+        if (
+            Application.Current?.ApplicationLifetime
+                is not IClassicDesktopStyleApplicationLifetime desktop
+            || desktop.MainWindow?.StorageProvider is not { } provider
+        )
+            throw new NullReferenceException("Missing StorageProvider instance.");
+
+        var files = await provider.OpenFilePickerAsync(
+            new FilePickerOpenOptions() { Title = "Open Text File", AllowMultiple = false }
+        );
+
+        return files?.Count >= 1 ? files[0] : null;
+    }
+
+    public async Task<IStorageFolder?> DoOpenFolderPickerAsync()
+    {
+        if (
+            Application.Current?.ApplicationLifetime
+                is not IClassicDesktopStyleApplicationLifetime desktop
+            || desktop.MainWindow?.StorageProvider is not { } provider
+        )
+            throw new NullReferenceException("Missing StorageProvider instance.");
+
+        var folder = await provider.OpenFolderPickerAsync(
+            new FolderPickerOpenOptions() { Title = "Open Text File", AllowMultiple = false }
+        );
+
+        return folder?.Count >= 1 ? folder[0] : null;
+    }
+}