Xamarin.Forms:如何下载图片，保存到本地并显示在屏幕上？

<Image x:Name="myImage" />

using System.Net.Http;

// 下载图片并保存到本地
private async Task DownloadAndSaveImage(string imageUrl, string fileName)
{
    HttpClient httpClient = new HttpClient();
    byte[] imageBytes = await httpClient.GetByteArrayAsync(imageUrl);

    // 保存图片到本地
    string localPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), fileName);
    File.WriteAllBytes(localPath, imageBytes);
}

// 显示本地图片
private void ShowLocalImage(string imagePath)
{
    myImage.Source = ImageSource.FromFile(imagePath);
}

private async void DownloadAndShowImage_Clicked(object sender, EventArgs e)
{
    string imageUrl = "https://example.com/image.jpg";
    string fileName = "image.jpg";

    await DownloadAndSaveImage(imageUrl, fileName);
    ShowLocalImage(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), fileName));
}