Function Module for Customer Master Details

To Get The Details Of The Customer, Here The Steps-
Step 1 - Create The Structure By Going To The T-Code SE11.
KUNNR
NAME1
STRAS
TELF1
TELF2
ADRNR
SMTP_ADDR
STREET
NAME_CO
CITY1
POST_CODE1
COUNTRY
TRANSPZONE
TEL_NUMBER
J_1IEXCD
J_1ICSTNO
J_1ILSTNO
J_1IPANNO

Step 2 - Create A Function Module By T-Code SE37
In Import Parameter Give IKUNNR.
Here Is The Source Code - 

FUNCTION ZCUST_INFO.
*"----------------------------------------------------------------------
*"*"LOCAL INTERFACE:
*"  IMPORTING
*"     VALUE(IKUNNR) TYPE  KNA1-KUNNR
*"  TABLES
*"      ITAB STRUCTURE  ZCUSTOMERINFO
*"----------------------------------------------------------------------

"GET THE ALL DETAILS FROM KNA1
SELECT
      KUNNR
      NAME1
      STRAS
      TELF1
      TELF2
      ADRNR
       INTO CORRESPONDING FIELDS OF ITAB
     FROM KNA1
     WHERE
     KUNNR = IKUNNR.
ENDSELECT.
IF SY-SUBRC <> 0.
ELSE.
APPEND ITAB.

"THIS WILL GIVE YOU EMAIL ADDRESS
LOOP AT ITAB INTO WA_ZEMAIL.
SELECT SMTP_ADDR
  INTO CORRESPONDING FIELDS OF ITAB
  FROM ADR6
  WHERE ADDRNUMBER = ITAB-ADRNR.
  ENDSELECT.
ENDLOOP.
APPEND ITAB.
"THIS WILL GIVE YOU THE ADDRESS
LOOP AT ITAB INTO WA_ZADDRESS1.
SELECT
  STREET
  NAME_CO
  CITY1
  POST_CODE1
  COUNTRY
  INTO CORRESPONDING FIELDS OF ITAB
  FROM ADRC
  WHERE ADDRNUMBER = ITAB-ADRNR.
  ENDSELECT.
ENDLOOP.
APPEND ITAB.
"THIS WILL GIVE YOU MOBILE AND TELEPHONE
LOOP AT ITAB INTO WA_ZTEL1.
SELECT
  TEL_NUMBER
  INTO CORRESPONDING FIELDS OF ITAB
  FROM ADR2
  WHERE ADDRNUMBER = ITAB-ADRNR AND R3_USER = '1'.
  ENDSELECT.
  ITAB-TELF1 = ITAB-TEL_NUMBER.
ENDLOOP.
APPEND ITAB.

LOOP AT ITAB INTO WA_ZTEL1.
SELECT
  TEL_NUMBER
  INTO CORRESPONDING FIELDS OF ITAB
  FROM ADR2
  WHERE ADDRNUMBER = ITAB-ADRNR AND R3_USER IN ('2','3').
  ENDSELECT.
  ITAB-TELF2 = ITAB-TEL_NUMBER.
ENDLOOP.
APPEND ITAB.

"THIS WILL GIVE EXCISE RELATED INFORMATION AND PAN NUMBER
LOOP AT ITAB INTO WA_ZBANK1.
SELECT
  J_1IEXCD
  J_1ICSTNO
  J_1ILSTNO
  J_1IPANNO
  INTO CORRESPONDING FIELDS OF ITAB
  FROM J_1IMOCUST
  WHERE KUNNR = IKUNNR.
  ENDSELECT.

ENDLOOP.
APPEND ITAB.

SORT ITAB DESCENDING BY SMTP_ADDR STREET NAME_CO J_1IEXCD.
DELETE ADJACENT DUPLICATES FROM ITAB COMPARING ADRNR.
ENDIF.

ENDFUNCTION.