public virtual extern void SetDefaultSaveFolder( [In] SafeNativeMethods.DEFAULTSAVEFOLDERTYPE dsft, [In, MarshalAs(UnmanagedType.Interface)] IShellItem si);
public virtual extern void GetDefaultSaveFolder( [In] SafeNativeMethods.DEFAULTSAVEFOLDERTYPE dsft, [In] ref Guid riid, [MarshalAs(UnmanagedType.Interface)] out IShellItem ppv);