ASPxFileManager - It is impossible to select a file on the server side when a custom FileSystemProvider is used

Hi Nikolay,

This issue is specific for a custom FileSystemProvider. It is reproduced only when setting IDs for the FileManagerFile and FileManagerFolder objects at a custom provider level. I will forward this issue to our R&D team and our developers will continue working on this problem. We will keep you informed of any progress.

For now, it is possible to work around the issue by not setting the FileManagerItem ID in your code. In this case, ID will be equal to the folder/file path. See the modified code from the E2900: ASPxFileManager - How to implement a LINQ to SQL based file system provider code example:

C#
protected void Page_PreRender(object sender, EventArgs e) {  
    ASPxFileManager1.SelectedFile = new FileManagerFile(ASPxFileManager1.CustomFileSystemProvider, "1.jpg");  
}  

C#
public override IEnumerable<FileManagerFile> GetFiles(FileManagerFolder folder) {  
    DbFileSystemItem dbFolderItem = FindDbFolderItem(folder);  

    // Current code that does not work:  
    //return  
    //    from dbItem in DataContext.DbFileSystemItems  
    //    where !dbItem.IsFolder && dbItem.ParentId == dbFolderItem.Id  
    //    select new FileManagerFile(this, folder, dbItem.Name, dbItem.Id.ToString());  

    // Code that should work:  
    return  
       from dbItem in DataContext.DbFileSystemItems  
       where !dbItem.IsFolder && dbItem.ParentId == dbFolderItem.Id  
       select new FileManagerFile(this, folder, dbItem.Name);  
}  
public override IEnumerable<FileManagerFolder> GetFolders(FileManagerFolder parentFolder) {  
    DbFileSystemItem dbFolderItem = FindDbFolderItem(parentFolder);  

    // Current code that does not work:  
    //return  
    //    from dbItem in FolderCache.Values  
    //    where dbItem.IsFolder && dbItem.ParentId == dbFolderItem.Id  
    //    select new FileManagerFolder(this, parentFolder, dbItem.Name, dbItem.Id.ToString());  

    // Code that should work:  
    return  
        from dbItem in FolderCache.Values  
        where dbItem.IsFolder && dbItem.ParentId == dbFolderItem.Id  
        select new FileManagerFolder(this, parentFolder, dbItem.Name);  
}  

I think the sample was a bit different back then when I implemented my provider, because I already don't have those IDs set in my code and I bet I did not remove them from the sample intentionally as I have no idea why they should or should not be assigned. Here's how the methods current look like in my code (in which the selection does not work):
public override IEnumerable<FileManagerFile> GetFiles(FileManagerFolder folder)
   {
     T dbFolderItem = FindDbFolderItem(folder);
     return from fileObj in StorageManager<T, DBManager>.getObjectsFromFolder(dbFolderItem.ID, _dbm, true, null, false)
            select new FileManagerFile(this, folder, fileObj.name);
   }
   public override IEnumerable<FileManagerFolder> GetFolders(FileManagerFolder parentFolder)
   {
     T dbFolderItem = FindDbFolderItem(parentFolder);
     return
         from dbItem in FoldersCache.Values
         where dbItem.IsFolder && dbItem.ParentID == dbFolderItem.ID
         select new FileManagerFolder(this, parentFolder, dbItem.name);
   }
As you see, the provider class is a generic in my case, because I use it for different tables with the same column names. The class definition is:
public class VirtualFileSystemProvider<T> : FileSystemProviderBase where T : class, IVirtualFileSystemEntry, new()
the "name" property I use here is my own property which simply returns file / folder name without any extra logic. The StorageManager<T, DBManager>.getObjectsFromFolder method is my method for retrieving files / folders from a virtual folder. I can provide you with my entire class source if needed, but as I said it has a lot of dependencies on other classes and besides cannot run without a DB.
Nickolay, Software Architect
ClickHelp - Online Documentation Tool
http://clickhelp.co

Hello Nickolay,

To find the cause of this issue, we need to research implementation details of your scenario. Would you please send me a simplified problematic page and the custom FileProvider class? If the provider requires some external data source, I will appreciate it if you provide it or update the provider so that we can test it without the additional data source.