Function Modules for creating programs (Useful when you are generating programs)
RS_PROGRAM_CHECK_NAME : To check program names if you are generating them.
RS_CORR_INSERT : To insert the correction request in the repository.
REPS_OBJECT_ACTIVATE : To activate repository objects, for example - to activate a newly generated program.
RS_DELETE_PROGRAM : To delete the program.
RS_ACCESS_PERMISSION : To lock or unlock a program.
Function Modules related to Date and Time Calculations
CALCULATE_DATE : Calculates the future date based on the input .
DATE_TO_DAY : Returns the Day for the entered date.
DATE_COMPUTE_DAY: Returns weekday for a date
DATE_GET_WEEK: Returns week for a date
Function Modules related to (ALV) ADVANCED LIST VIEWER
REUSE_ALV_LIST_DISPLAY: ABAP List viewer (LIST DISPLAY)
REUSE_ALV_GRID_DISPLAY: ALV GridControl full screen
REUSE_ALV_FIELDCATALOG_MERGE: Create field catalog from dictionary structure or internal table
Function Module related to Change Tracking
CHANGEDOCUMENT_READ_HEADERS : Read and format change documents
DAY_ATTRIBUTES_GET : Returns attributes for a range of dates specified
MONTHS_BETWEEN_TWO_DATES : To get the number of months between the two dates.
END_OF_MONTH_DETERMINE_2 : Determines the End of a Month.
HR_HK_DIFF_BT_2_DATES : Find the difference between two dates in years, months and days.
FIMA_DAYS_AND_MONTHS_AND_YEARS : Find the difference between two dates in years, months and days.
MONTH_NAMES_GET : Get the names of the month
WEEK_GET_FIRST_DAY : Get the first day of the week
HRGPBS_HESA_DATE_FORMAT : Format the date in dd/mm/yyyy format
SD_CALC_DURATION_FROM_DATETIME : Find the difference between two date/time and report the difference in hours
L_MC_TIME_DIFFERENCE : Find the time difference between two date/time
HR_99S_INTERVAL_BETWEEN_DATES : Difference between two dates in days, weeks, months
LAST_DAY_OF_MONTHS : Returns the last day of the month
DATE_CHECK_PLAUSIBILITY :Check for the invalid date.
DATE_2D_TO_4D_CONVERSION :Year entry: 2-character to 4-character.
DAY_IN_WEEK :Input date and will give the name of the day 1-monday,2-Tuesday....
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Function Modules Related To Formatting
CLOI_PUT_SIGN_IN_FRONT : Displays the negative sign in front of the numeral
RKD_WORD_WRAP : Wrap text into several lines
CONVERSION_EXIT_ALPHA_INPUT : Pad zeros to the number at the left
CONVERSION_EXIT_ALPHA_OUTPUT : Eliminate zeros to the number at the left
Function Modules Related To Dialog Prompts
POPUP_TO_CONFIRM : Displays a popup dialog with a user defined message for confirmation
POPUP_TO_GET_VALUE : Displays a popup dialog requesting a value for a particular table-fieldname
SAPGUI_PROGRESS_INDICATOR : Displays a progress bar with text to denote the percentage of completion and status
FILENAME_GET : Displays a popup dialog to get the presentation server filename
F4_DATE : Displays a popup dialog to choose date
GUI_UPLOAD : Upload a file from the presentation server
POPUP_TO_SELECT_MONTH : Display a pop-up to select a month
Function modules related to RFC communication
RFC_CONNECTION_CLOSE : Close a RFC connection
RFC_GET_SYSTEM_INFO : Give system's information of a remote system
Function modules related to reading/writing files
FILE_READ_AND_CONVERT_SAP_DATA: Uploads the file from either presentation or application server into an internal table
SUBST_GET_FILE_LIST: To get the list of files from Application Server.
ALSM_EXCEL_TO_INTERNAL_TABLE : Legacy Data Transfer w/ Excel
Function Modules related to sending emails
SO_NEW_DOCUMENT_ATT_SEND_API1 - Sends emails with texts and attachments
SO_NEW_DOCUMENT_SEND_API1 - Sends emails with texts.
Function Modules related to F4 Help
F4IF_INT_TABLE_VALUE_REQUEST - F4 help also returning the value to be displayed in internal table
Read here Function Module for Encryption and Decryption