avalonia-services

Avalonia Platform Services

Overview

Platform services are accessed via the TopLevel class (root of visual tree — typically Window or PopupRoot).

var topLevel = TopLevel.GetTopLevel(this); // 'this' = any attached control

Returns null if control is not yet attached to visual tree. Call in OnAttachedToVisualTree or later.

Clipboard

var clipboard = TopLevel.GetTopLevel(this)?.Clipboard;

// Write text
await clipboard!.SetTextAsync("Hello, world");

// Write custom data object
var data = new DataObject();
data.Set("application/x-myformat", myObject);
data.Set(DataFormats.Text, "fallback text");
await clipboard.SetDataObjectAsync(data);

// Read text
var text = await clipboard!.GetTextAsync(); // null if no text on clipboard

// Read custom format
var formats = await clipboard!.GetFormatsAsync(); // string[]
var raw = await clipboard!.GetDataAsync("application/x-myformat");

// Clear
await clipboard!.ClearAsync();

File Dialogs (StorageProvider)

var storage = TopLevel.GetTopLevel(this)?.StorageProvider;

Open file(s):

var files = await storage!.OpenFilePickerAsync(new FilePickerOpenOptions
{
    Title = "Open File",
    AllowMultiple = false,
    FileTypeFilter = new[]
    {
        new FilePickerFileType("Images")
        {
            Patterns = new[] { "*.png", "*.jpg", "*.jpeg", "*.webp" },
            MimeTypes = new[] { "image/png", "image/jpeg" }
        },
        new FilePickerFileType("All Files") { Patterns = new[] { "*" } }
    },
    SuggestedStartLocation = await storage.TryGetWellKnownFolderAsync(WellKnownFolder.Pictures)
});

if (files.Count > 0)
{
    await using var stream = await files[0].OpenReadAsync();
    var bitmap = new Bitmap(stream);
}

Built-in FilePickerFileTypes: All, TextPlain, Pdf, Images

Save file:

var file = await storage!.SaveFilePickerAsync(new FilePickerSaveOptions
{
    Title = "Save As",
    DefaultExtension = "txt",
    SuggestedFileName = "untitled",
    FileTypeChoices = new[]
    {
        new FilePickerFileType("Text Files") { Patterns = new[] { "*.txt" } },
        new FilePickerFileType("All Files") { Patterns = new[] { "*" } }
    }
});

if (file is not null)
{
    await using var stream = await file.OpenWriteAsync();
    await using var writer = new StreamWriter(stream);
    await writer.WriteAsync(content);
}