Date according to user requirement

Question

Hi experts
I have a selection-screen date field when user enter date with the help of F4 it shows error message like this
Input date format like this                 :   09/01/2010
Please Enter date in the format       :  __.__.____   like this 
is there any function modules  to convert date like this format .
Thanks & Regards
Siva Krishna.

Answer 1

To solve this purpose, a function module has been created which takes the date and format (in which date needs to be converted) as input and gives the date in the desired format as output. It also raises an exception if the format is incorrect.
For achieving this functionality, a ztable is to be created which contains all the possible formats of  a date. Then the format given on the screen is to be validated against this table.
STRUCTURE OF THE FUNCTION MODULE
FUNCTION zdummy_date_conv.
""Local Interface:
*"  IMPORTING
*"     REFERENCE(DATE) TYPE  SYDATUM
*"     REFERENCE(FORMAT) TYPE  CHAR15
*"  EXPORTING
*"     REFERENCE(DATE_FINAL) TYPE  CHAR15
*"  EXCEPTIONS
*"      INCORRECT_FORMAT
POSSIBLE DATE FORMATS
DATE FORMATS
       DD.MM.YY
MM.DD.YY
MM.YY.DD
YY.MM.DD
YY.DD.MM
DD.YY.MM
DD-MM-YY
MM-DD-YY
MM-YY-DD
YY-MM-DD
YY-DD-MM
DD-YY-MM
DD/MM/YY
MM/DD/YY
MM/YY/DD
YY/MM/DD
YY/DD/MM
DD/YY/MM
DDMMYY
MMDDYY
MMYYDD
YYMMDD
YYDDMM
DDYYMM
DD.MMM.YY
MMM.DD.YY
MMM.YY.DD
YY.MMM.DD
YY.DD.MMM
DD.YY.MMM
DD-MMM-YY
MMM-DD-YY
MMM-YY-DD
YY-MMM-DD
YY-DD-MMM
DD-YY-MMM
DD/MMM/YY
MMM/DD/YY
MMM/YY/DD
YY/MMM/DD
YY/DD/MMM
DD/YY/MMM
DDMMMYY
MMMDDYY
MMMYYDD
YYMMMDD
YYDDMMM
DDYYMMM
DD.MM.YYYY
MM.DD.YYYY
MM.YYYY.DD
YYYY.MM.DD
YYYY.DD.MM
DD.YYYY.MM
DD-MM-YYYY
MM-DD-YYYY
MM-YYYY-DD
YYYY-MM-DD
YYYY-DD-MM
DD-YYYY-MM
DD/MM/YYYY
MM/DD/YYYY
MM/YYYY/DD
YYYY/MM/DD
YYYY/DD/MM
DD/YYYY/MM
DDMMYYYY
MMDDYYYY
MMYYYYDD
YYYYMMDD
YYYYDDMM
DDYYYYMM
DD.MMM.YYYY
MMM.DD.YYYY
MMM.YYYY.DD
YYYY.MMM.DD
YYYY.DD.MMM
DD.YYYY.MMM
DD-MMM-YYYY
MMM-DD-YYYY
MMM-YYYY-DD
YYYY-MMM-DD
YYYY-DD-MMM
DD-YYYY-MMM
DD/MMM/YYYY
MMM/DD/YYYY
MMM/YYYY/DD
YYYY/MMM/DD
YYYY/DD/MMM
DD/YYYY/MMM
DDMMMYYYY
MMMDDYYYY
MMMYYYYDD
YYYYMMMDD
YYYYDDMMM
DDYYYYMMM      
CODE OF FUNCTION MODULE
FUNCTION zdummy_date_conv.
""Local Interface:
*"  IMPORTING
*"     REFERENCE(DATE) TYPE  SYDATUM
*"     REFERENCE(FORMAT) TYPE  CHAR15
*"  EXPORTING
*"     REFERENCE(DATE_FINAL) TYPE  CHAR15
*"  EXCEPTIONS
*"      INCORRECT_FORMAT
Local variables declaration
  DATA: l_y1         TYPE numc1,
        l_y2         TYPE numc1,
        l_y3         TYPE numc1,
        l_y4         TYPE numc1,
        l_m1         TYPE numc1,
        l_m2         TYPE numc1,
        l_d1         TYPE numc1,
        l_d2         TYPE numc1,
        l_len        TYPE int1,
        l_ctr        TYPE int1,
        w_t247       TYPE t247,
        l_flag_m1    TYPE char1,
        l_flag_init  TYPE char1,
        l_flag_d     TYPE char1,
        l_flag_y     TYPE char1,
        l_format     TYPE char15,
        l_final_date TYPE char15.
Local constants declaration
  CONSTANTS: c_d    TYPE char1 VALUE 'D',
             c_m    TYPE char1 VALUE 'M',
             c_y    TYPE char1 VALUE 'Y',
             c_mmm  TYPE char3 VALUE 'MMM',
             c_yyyy TYPE char4 VALUE 'YYYY'.
Checking the format given by user.
  SELECT SINGLE zformat
    FROM zformat_date
    INTO l_format
   WHERE zformat = format.
  IF sy-subrc EQ 0.
Processing Logic of the routine
    l_y1 = date+0(1).
    l_y2 = date+1(1).
    l_y3 = date+2(1).
    l_y4 = date+3(1).
    l_m1 = date+4(1).
    l_m2 = date+5(1).
    l_d1 = date+6(1).
    l_d2 = date+7(1).
    l_len = STRLEN( format ).
    CLEAR : l_flag_m1, l_flag_init, l_flag_d,l_flag_y.
    WHILE l_ctr < l_len.
      IF format+l_ctr(1) = c_m.
        IF NOT format CS c_mmm.
          l_final_date+l_ctr(1) = l_m1.
          l_ctr = l_ctr + 1.
          l_flag_m1 = l_flag_m1 + 1.
          l_final_date+l_ctr(1) = l_m2.
          l_ctr = l_ctr + 1.
          l_flag_m1 = l_flag_m1 + 1.
        ELSE.
          SELECT SINGLE * FROM t247 INTO w_t247
             WHERE spras = sy-langu
               AND  mnr  = date+4(2).
          IF sy-subrc EQ 0.
            l_final_date+l_ctr(3) = w_t247-ktx.
            l_ctr = l_ctr + 3.
          ENDIF.
        ENDIF.
      ELSEIF format+l_ctr(1) = c_y.
        IF format CS c_yyyy.
          l_final_date+l_ctr(1) = l_y1.
          l_ctr = l_ctr + 1.
          l_final_date+l_ctr(1) = l_y2.
          l_ctr = l_ctr + 1.
          l_final_date+l_ctr(1) = l_y3.
          l_ctr = l_ctr + 1.
          l_final_date+l_ctr(1) = l_y4.
          l_ctr = l_ctr + 1.
        ELSE.
          l_final_date+l_ctr(1) = l_y3.
          l_ctr = l_ctr + 1.
          l_flag_y = l_flag_y + 1.
          l_final_date+l_ctr(1) = l_y4.
          l_ctr = l_ctr + 1.
          l_flag_y = l_flag_y + 1.
        ENDIF.
      ELSEIF format+l_ctr(1) = c_d.
        l_final_date+l_ctr(1) = l_d1.
        l_ctr = l_ctr + 1.
        l_flag_d = l_flag_d + 1.
        l_final_date+l_ctr(1) = l_d2.
        l_ctr = l_ctr + 1.
        l_flag_d = l_flag_d + 1.
      ELSE.
        l_final_datel_ctr(1) = formatl_ctr(1).
        l_ctr = l_ctr + 1.
      ENDIF.
      IF NOT l_final_date IS INITIAL.
        date_final = l_final_date.
      ENDIF.
    ENDWHILE.
  ELSE.
    CLEAR date_final.
    RAISE incorrect_format.
  ENDIF.
ENDFUNCTION.