VB.NET - Check if URL is a directory or file

问题:

Is there a way, in VB.NET, to check if a URL is a directory? I've seen a lot of methods of checking if a local path is a directory but what about a remote url (i.e. http://website.com/foo) I read that some plain text files have no extension so I need a solution other than checking what if the file name contains a space or something.

回答1:

You can use FileAttributes class:

'get the file attributes for file or directory
FileAttributes attr = File.GetAttributes("c:\\Temp")

'detect whether its a directory or file
If ((attr & FileAttributes.Directory) = FileAttributes.Directory) Then
    MessageBox.Show("Its a directory")
Else
    MessageBox.Show("Its a file")
End IF

Or you can use the Uri class:

Private IsLocalPath(Byval p As String) As Boolean
  Return New Uri(p).IsFile
End Function

You can enhance this method to include support for certain invalid URIs:

Private IsLocalPath(Byval p As String) As Boolean
  If (p.StartsWith("http:\\")) Then      
    Return False
  End IF

  Return New Uri(p).IsFile
End Function

回答2:

The only solution I can think of is to try to download the file from the Internet, if the download succeeded So it is a file, otherwise it is not a file (but you don't know for sure that this is a directory).

回答3:

This worked for me...

If System.IO.Path.HasExtension(FileAddress.Text)  Then
   MessageBox.Show("Its a file")
Else
   MessageBox.Show("Its a directory")
End IF