Win32 - Fastest way to determine if file exists in a folder based on a a folders PIDL?

Question

Using windows/shell api (atl be ok), given a folder's PIDL, what's the fastest way to check if a file exists in that folder?

Answer 1

Not sure if this is the fastest way, but it is fairly straight-forward:

Convert the PIDL to an IShellFolder (if you don't already have one) using SHGetDesktopFolder() and IShellFolder::BindToObject(), or just SHBindToObject(), or other related function. And then call the folder's IShellFolder::ParseDisplayName() (and, if needed, IShellFolder::GetAttributesOf()) for the child filename. If an error occurs, the file does not exist.

Alternatively, convert the PIDL to an IShellItem (if you don't already have one) using SHCreateItemFromIDList(), and then use SHCreateItemFromRelativeName() (and, if needed, IShellItem::GetAttributes(SFGAO_VALIDATE)) for the child filename. Again, if an error occurs (or the attributes don't validate), the file does not exist.