Message options

Question

Please let me know how do I validate a parameter on a selection screen by using messaging options.
for eg..
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE text-001.
SELECT-OPTIONS: s_mru FOR te422-termschl.
SELECTION-SCREEN END OF BLOCK b1.
PARAMETER : p_ins TYPE i DEFAULT 150.
suppose I need to validate for both the fields
1. s_mru (it should not accept a value which is not in the table field te422-termschl)
2. p_ins (the output screen should not come if the value of p_ins is less than 1)
kindly show me the flow of code ....
thx...

Answer 1

Report test.
AT SELECTION-SCREEN.
*Validate addrnumber
AT SELECTION-SCREEN ON p_addr.
  PERFORM f1003_validate_addr.
*&      Form  f1003_validate_addr
      Validate addr
FORM f1003_validate_addr.
  DATA lv_addr TYPE ADRC-ADDRNUMBER.
Check for valid addr
  CHECK NOT p_addr IS GE 0.
  CLEAR lv_addr.
  SELECT SINGLE addrnumber INTO lv_addr FROM adrc WHERE 
                             ADDRNUMBER  IN p_addr.
  IF sy-subrc NE 0.
    MESSAGE e000 WITH text-016.
  ENDIF.
ENDFORM.                    " f1003_validate_addr
Regards,
Anjali