Input Routine

 BBS: Inland Empire Archive
Date: 12-31-92 (07:53)             Number: 386
From: TOM HAMMOND                  Refer#: NONE
  To: IMRAN HAYAT                   Recvd: NO  
Subj: Input Routine                  Conf: (2) Quik_Bas

IH>In QBasic, how can you limit the amount that the cursor can travel in
   an INPUT statement?

What you have to do is to not use INPUT but build yourself an input
routine which takes each character as it is entered and appends it to
the end of a string which it builds as characters are entered.  Then,
you can (with each subsequent entry) check the length of the input
string (the one you're building) and just not allow further input when
the maximum field length has been met.

Here's an input routine which was posted a while back by Margaret Romao.
It may help you get started.  I have at least two other input routines
but both are MUCH longer (15k and 50k respectively) than this one.  They
would take several messages to post.  Will consider seinding them if you
REALLY need them, but please try this one first.  I'm sure you'll get
suggestions from other users too.  Good Luck

Tom Hammond

'Date: 02-18-92 (10:54)             Number: 6260
'From: MARGARET ROMAO               Refer#: NONE
'Subj: Input replacement              Conf: (13) QuickBasic
'
-----
'I saw a request for the following information, so here's an input
'replacement.  The VAL function may be used to convert the variable Inp$
'to a numeric value.  Sorry about the GOTO's.

DECLARE SUB Parser (Inp$, Prompt$, Row%, Col%, Length%, Fore%, Back%)

        ' A little sample code to show how to call the procedure
        COLOR 15, 1: CLS
        Parser Inp$, "Enter some text: ", 4, 4, 8, 15, 1
        LOCATE 6, 4: PRINT "You entered: "; Inp$

SUB Parser (Inp$, Prompt$, Row%, Col%, Length%, Fore%, Back%)
    CPos% = LEN(Inp$)
    InpLength% = LEN(Inp$)
    COLOR Fore%, Back%
    LOCATE Row%, Col%, 1, 10, 11: PRINT Prompt$;
GN1:
    DO: InKy$ = INKEY$: LOOP UNTIL LEN(InKy$)
    IF LEN(InKy$) = 1 THEN
        SELECT CASE ASC(InKy$)
            CASE 32 TO 126    ' std. alphanumeric keys
                IF InpLength% < Length% THEN
                    temp1$ = LEFT$(Inp$, CPos%)
                    temp2$ = RIGHT$(Inp$, InpLength% - CPos%)
                    Inp$ = temp1$ + InKy$ + temp2$
                    InpLength% = InpLength% + 1
                    CPos% = CPos% + 1
                    LOCATE Row%, (Col% + LEN(Prompt$))
                    PRINT Inp$
                    LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
                    GOTO GN1
                END IF
            CASE 8     'Backspace key
                IF InpLength% > 0 AND CPos% > 0 THEN
                    temp1$ = LEFT$(Inp$, CPos% - 1)
                    temp2$ = RIGHT$(Inp$, InpLength% - CPos%)
                    Inp$ = temp1$ + temp2$
                    InpLength% = InpLength% - 1
                    CPos% = CPos% - 1
                    LOCATE Row%, (Col% + LEN(Prompt$))
                    PRINT Inp$ + CHR$(32)
                    LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
                END IF
            CASE 13    ' <C/R>
                GOTO GNE
            CASE ELSE
                SOUND 50, 3
                GOTO GN1
        END SELECT
    ELSE
        InKy$ = (RIGHT$(InKy$, 1))
        SELECT CASE ASC(InKy$)
            CASE 75    'right arrow
                IF CPos% > 0 THEN
                    CPos% = CPos% - 1
                    LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
                    GOTO GN1
                END IF
            CASE 77    'left arrow
                IF CPos% < InpLength% THEN
                    CPos% = CPos% + 1
                    LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
                    GOTO GN1
                END IF
            CASE 71    'home key
                CPos% = 0
                LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
            CASE 79    'end key
                CPos% = InpLength%
                LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
            CASE 83    'del key
                IF InpLength% > 0 AND CPos% < InpLength% THEN
                    temp1$ = LEFT$(Inp$, CPos%)
                    temp2$ = RIGHT$(Inp$, InpLength% - CPos% - 1)
                    Inp$ = temp1$ + temp2$
                    InpLength% = InpLength% - 1
                    LOCATE Row%, (Col% + LEN(Prompt$))
                    PRINT Inp$ + CHR$(32)
                    LOCATE Row%, (Col% + LEN(Prompt$)) + CPos%
                END IF
            CASE ELSE
                SOUND 50, 3
                GOTO GN1
        END SELECT
    END IF
    IF InpLength% >= Length% THEN
        IF Length% < 1 THEN GOTO GN1
        SOUND 800, 1
        GOTO GN1
    END IF
    GOTO GN1

GNE:
    LOCATE Row%, (Col% + LEN(Prompt$)), 0

END SUB

THE END!
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 * Origin: Night Shift BBS (314)635-7588 HST 14.4 (1:289/15)