Question

我无法在Xamarin.forms文件中保存文件，以便用户可以在下载或文档中看到它。我已经设法使用 PCL 保存到隐藏文件中，但是我需要用户能够看到保存的文件。我可以用来访问可见文件夹并将文件保存在那里吗？

这不起作用：

string writeData = convertToString(data);
string documentsPath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
string localFilename = "Data.csv";
string localPath = Path.Combine(documentsPath, localFilename);
File.WriteAllText(localPath, writeData);

Answer 1

当然，您可以将文件保存到可见文件夹。根据文档： external storage。例如，如果要将文件保存到“文档”文件夹，则可以按以下方式获取路径：

processed_names = (name.split('.')[0] for name in done_match)
d = dict.from_keys(processed_names, 1)

希望对您有帮助！

Answer 2

在iOS和Android上采用不同的解决方案，并使用depencdeny加以区分。

Android

     public void saveFile(string fileName, string text)
     {
        string DocumentPath = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryDownloads).AbsolutePath;
        string filePath = Path.Combine(DocumentPath, fileName);
        File.WriteAllText(filePath, text);
     }

iOS：找到了一些代码，可以将其保存在iCLoud驱动器https://xamarinhelp.com/share-dialog-xamarin-forms/上：

     public class Share : IShare
{
    // MUST BE CALLED FROM THE UI THREAD
    public async Task Show(string filePath)
    {
        var items = new NSObject[] { NSUrl.FromFilename(filePath) };
        var activityController = new UIActivityViewController(items, null);
        var vc = GetVisibleViewController();

        NSString[] excludedActivityTypes = null;

        if (excludedActivityTypes != null && excludedActivityTypes.Length > 0)
            activityController.ExcludedActivityTypes = excludedActivityTypes;

        if (UIDevice.CurrentDevice.CheckSystemVersion(8, 0))
        {
            if (activityController.PopoverPresentationController != null)
            {
                activityController.PopoverPresentationController.SourceView = vc.View;
            }
        }
        await vc.PresentViewControllerAsync(activityController, true);
    }

    UIViewController GetVisibleViewController()
    {
        var rootController = UIApplication.SharedApplication.KeyWindow.RootViewController;

        if (rootController.PresentedViewController == null)
            return rootController;

        if (rootController.PresentedViewController is UINavigationController)
        {
            return ((UINavigationController)rootController.PresentedViewController).TopViewController;
        }

        if (rootController.PresentedViewController is UITabBarController)
        {
            return ((UITabBarController)rootController.PresentedViewController).SelectedViewController;
        }

        return rootController.PresentedViewController;
    }
}

如何保存文件以便用户查看？

2 个答案: