Isn't this "just" handled by the provider and the Content/MediaService where you store the file using a stream?

var doc = ApplicationContext.Current.Services.ContentService.GetById(1234);
using (var fs = System.IO.File.OpenRead(mediaFile.FilePath))
                                    {
                                        doc.SetValue("file alias", "fileName", fs);
                                        isDirty = true;
                                    }

Hi RIchard,
I am not 100% sure about that.

Here are some snippets/findings I have found:

var fs = FileSystemProviderManager.Current.GetFileSystemProvider<MediaFileSystem>();

//Line 81 of FileUploadPropertyValueEditor.cs
fs.DeleteFile(fs.GetRelativePath(toRemove), true);

//Line 129 of FileUploadPropertyValueEditor.cs
var umbracoFile = UmbracoMediaFile.Save(fileStream, fileName);

//Method in UmbracoMediaFile.cs
public static UmbracoMediaFile Save(Stream inputStream, string path)
{
    var fs = FileSystemProviderManager.Current.GetFileSystemProvider<MediaFileSystem>();
    fs.AddFile(path, inputStream);

    return new UmbracoMediaFile(path);
}

But the magic seems to be in the class FileSystemWrapper.cs with methods like so:

• Get Directories
• Delete Directory
• Get Files
• etc...

Example comes from the "official" documentation http://our.umbraco.org/documentation/Reference/Management-v6/Models/Content

CMSImport V3 is using that as well. I think that method talks to the underlying Filesystemprovider used in filesystem code you found.

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