'===========================================================================
' Subject: FILE PAGING DEMO                  Date: 01-05-96 (00:00)       
' Author:  Raymond Joh                       Code: QB, QBasic, PDS        
' Origin:  Dslayer@gnn.com                 Packet: DOS.ABC
'===========================================================================
'=============================FILE PAGING DEMO===============================
'RAYMOND JOH
'COMPUTERS SOLUTIONS
'PANAMA CITY,FLA.
'
'THIS PROGRAM IS DESIGNED TO BE AS FLEXIBLE AND USER FRIENDLY AS POSSIBLE.
'THE "USER VARIABLES" SECTION BELOW, ALLOWS YOU PLACE YOUR TEXT TO BE PAGED
'ANYWHERE ON THE SCREEN.BY REMOVING MY SCREEN.GRAPHICS SUB AND PLACING THE
'THE REST OF THIS DEMO IN YOUR PROGRAM,YOU CAN EASILY PAGE ANY FILE. THIS
'EXAMPLE PAGES YOUR C: DRIVE DIRECTORY.
'
'DONATED TO THE PUBLIC DOMAIN 1/05/95
'
DECLARE SUB SCREEN.GRAPHICS (CURPAGE%, TOTALPAGES%, FILESIZE%, DL%, LIN%, LP%, DLI%)
DECLARE SUB PAGE.1 (EXAMFILE$(), COUNT%, PAGE%, DL%, LIN%, LP%, DLI%)
DECLARE SUB PAGEUP (EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%)
DECLARE SUB PAGEDOWN (EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%)
DECLARE FUNCTION GETKEY% ()
CONST UPKEY = 72 * 256, DOWNKEY = 80 * 256, PGDN = 81 * 256, PGUP = 73 * 256
CONST ESCAPE = 27
SCREEN 12                       'SCREEN MODE OF CHOICE OF AUTHOR
'
'                      #####################
'                      ##  USER VARIBLES  ##
'                      #####################
LIN% = 22                    'NUMBER OF FILES FOR DISPLAY:CAN BE UP TO 26
DL% = 3                      'BEGINNING DISPLAY LINE,ADJUST ACCORDINGLY
LP% = 15                     'BEGINNING LINE POSITION,ADJUST ACCORDINGLY

'                       ######################
'                       ## CREATE .DAT FILE ##
'                       ######################
'
SHELL "DIR C:/ON/B>C:\DOS\DATA.DAT"            'OR CREATE YOUR OWN
'                  ###############################
'                  ## READ .DAT FILE INTO ARRAY ##
'                  ###############################
DIM EXAMFILE$(1 TO 500)                        'DIM ARRAYS
OPEN "C:\DOS\DATA.DAT" FOR INPUT AS #1         'OPEN .DAT FILE
OPEN "C:\DOS\DOSDATA.DAT" FOR OUTPUT AS #2     'DETERMINE FILE SIZE
FILESIZE% = 1                                  'BY COPYING TO FILE #2
DO
  LINE INPUT #1, EXAMFILE$(FILESIZE%)
  PRINT #2, EXAMFILE$(FILESIZE%)
  FILESIZE% = FILESIZE% + 1
LOOP UNTIL EOF(1)
FILESIZE% = FILESIZE% - 1
CLOSE (1)
'                    ##########################
'                    ## CALL SCREEN GRAPHICS ##
'                    ##########################
DLI% = DL%                              'NOTE INITIAL LINE POSITION
TP = FILESIZE% / LIN%                   'COUNT TOTAL PAGES
CURPAGE% = 1                            'BEGINNING PAGE NUMBER
IF TP > INT(TP) THEN TOTALPAGES% = INT(TP) + 1
CALL SCREEN.GRAPHICS(CURPAGE%, TOTALPAGES%, FILESIZE%, DL%, LIN%, LP%, DLI%)
CALL PAGE.1(EXAMFILE$(), COUNT%, PAGE%, DL%, LIN%, LP%, DLI%)

DO
  KEYIN% = GETKEY%                      'INITIATE INKEY% BY CALLING GETKEY%
  SELECT CASE KEYIN%                    '
    CASE DOWNKEY, PGDN                  'DOWN-ARROW OR PGDN PRESSED
      PAGEDOWN EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%
    CASE UPKEY, PGUP                    'UP-ARROW OR PGUP PRESSED
      PAGEUP EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%
    CASE ESCAPE                         'CASE ESCAPE--->>>GOODBYE
      CLOSE (2)
      KILL "C:\DOS\DATA.DAT"
      KILL "C:\DOS\DOSDATA.DAT"
      SYSTEM
  END SELECT
LOOP

'                         #####################
'                         ## FUNCTION GETKEY ##
'                         #####################
'
FUNCTION GETKEY%
  DO
    KEYIN$ = INKEY$
  LOOP UNTIL LEN(KEYIN$)
  GETKEY% = CVI(KEYIN$ + CHR$(0))
END FUNCTION

'                        ########################
'                        ## SUB-ROUTINE PAGE.1 ##
'                        ########################
'
SUB PAGE.1 (EXAMFILE$(), COUNT%, CURPAGE%, DL%, LIN%, LP%, DLI%)
FOR N% = 1 TO LIN%
  COLOR 12: LOCATE DL% + N%, LP%
  PRINT EXAMFILE$(N%)
  COUNT% = COUNT% + 1
  PAGE% = PAGE% + 1
NEXT N%
END SUB

'                       ##########################
'                       ## SUB-ROUTINE PAGEDOWN ##
'                       ##########################
'
SUB PAGEDOWN (EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%)
IF CURPAGE% < TOTALPAGES% THEN
  IF LASTKEY% = 1 THEN COUNT% = COUNT% + LIN%
  CLS : COLOR 12
  CURPAGE% = CURPAGE% + 1
  FOR F% = 1 + COUNT% TO COUNT% + LIN%
    SCREEN.GRAPHICS CURPAGE%, TOTALPAGES%, FILESIZE%, DL%, LIN%, LP%, DLI%
    LOCATE DL% + (F% - COUNT%), LP%: PRINT EXAMFILE$(F%)
  NEXT F%
  LASTKEY% = 0
  COUNT% = COUNT% + LIN%
END IF
END SUB

'                        ########################
'                        ## SUB-ROUTINE PAGEUP ##
'                        ########################
'
SUB PAGEUP (EXAMFILE$(), FILESIZE%, COUNT%, TOTALPAGES%, CURPAGE%, LASTKEY%, DL%, LIN%, LP%, DLI%)
IF CURPAGE% > 1 THEN
  CLS : COLOR 12
  CURPAGE% = CURPAGE% - 1
  IF LASTKEY% = 1 THEN COUNT% = COUNT% - LIN%
  IF LASTKEY% = 0 THEN COUNT% = COUNT% - (2 * LIN%): LASTKEY% = LASTKEY% + 1
  SCREEN.GRAPHICS CURPAGE%, TOTALPAGES%, FILESIZE%, DL%, LIN%, LP%, DLI%
  FOR F% = 1 + COUNT% TO COUNT% + LIN%
    LOCATE DL% + (F% - COUNT%), LP%: PRINT EXAMFILE$(F%)
  NEXT F%
END IF
END SUB

'                    #################################
'                    ## SUB-ROUTINE SCREEN.GRAPHICS ##
'                    #################################
'
SUB SCREEN.GRAPHICS (CURPAGE%, TOTALPAGES%, FILESIZE%, DL%, LIN%, LP%, DLI%)
COLOR 3: LOCATE 2, 33: PRINT " PAGE "; CURPAGE%; "OF"; TOTALPAGES%
LINE (50, 36)-(580, 36), 12
LINE (50, 37)-(580, 37), 15
LINE (50, 38)-(580, 38), 7
LOCATE 27, 23: PRINT "<DOWN ARROW> OR <PGDN> TO PAGE DOWN"
LOCATE 28, 23: PRINT "  <UP ARROW> OR <PGUP> TO PAGE UP"
LINE (50, 406)-(580, 406), 12
LINE (50, 407)-(580, 407), 15
LINE (50, 408)-(580, 408), 7
COLOR 15:
LOCATE 12, 50: PRINT "TOTAL FILESIZE ="; FILESIZE%
LOCATE 13, 45: PRINT "TEXT STARTS ON LINE ="; DLI%
LOCATE 14, 47: PRINT "TEXT ENDS ON LINE ="; LIN% + DLI%
COLOR 12
END SUB