static extern void PathStripPath([In,Out] StringBuilder pszPath);

<DllImport("shlwapi.dll", EntryPoint:="PathStripPathW",  SetLastError:=True, CharSet:=CharSet.Unicode)> _

Public Sub PathStripPath(<MarshalAs(UnmanagedType.LPTStr)>pszPath As System.Text.StringBuilder)

Public Declare Sub PathStripPath Lib "shlwapi" Alias "PathStripPathA" _

PathStripPath(str);

Win32.API.Shlwapi.PathStripPath(strFile)