Hi Meenakshi,
you can use case statement.
loop at lt_SWPSTEPLOG into ls_SWPSTEPLOG.
case ls_swpsteplog-returntyp.
WHEN 'RC'
START_DATE = LOG_DATE.
START_TIME = LOG_TIME.
WHEN 'EV'.
wi_id = ls_SWPSTEPLOG1-wi_id
task_id = ls_SWPSTEPLOG1-task_id
ENDCASE.
ENDLOOP.
Regards,
Venkat.