Update values in dynpro fields

Data: dyfields LIKE dynpread OCCURS 1 WITH HEADER LINE.

dyfields-fieldname =  'PDPLA-VON_DATE'.
dyfields-fieldvalue = l_datestr.
APPEND dyfields.


CALL FUNCTION 'DYNP_VALUES_UPDATE'
    EXPORTING
      dyname               = sy-cprog
      dynumb               = sy-dynnr
    TABLES
      dynpfields           = dyfields
    EXCEPTIONS
      invalid_abapworkarea = 1
      invalid_dynprofield  = 2
      invalid_dynproname   = 3
      invalid_dynpronummer = 4
      invalid_request      = 5
      no_fielddescription  = 6
      undefind_error       = 7
      OTHERS               = 8.
  IF sy-subrc <> 0.
  ENDIF.