Re: Large directories... DirectoryInfo or Win32 API?

From: Robert Jordan (robertj_at_gmx.net)
Date: 10/01/04 

Date: Fri, 01 Oct 2004 14:04:23 +0200

Justin Rogers wrote:

> Internally they are doing the Win32 API calls for you. However, they are
> also allocating a LOT of array space to do it. Specifically they are making
> an extra copy, which probably isn't necessary, and there is a possible
> resource leak in that particular method that they aren't accounting for.

Really weird is the fact that Directory.GetFiles returns a string array
with fully qualified file names. Imagine you want to enumerate

c:\documents and settings\
   \SomeUsername
     \Program Data
       \some scary long company name
         \even longer fancy product name

or some huge UNC path hierarchies

\\server\share\public\org\unit\projekt\subproject\trash\

DirectoryInfo.GetFiles returns an array of FileInfo which
is probably even larger then the fully qualified file name.

I wonder why MS didn't desiged that API to return an object
"FileList", whose enumerator calls Win32's FindNextFile
just in time (or on demand).

bye
Rob

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