View source for PDS(7.1) Procedures

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'''QB64''' was created to be compatible with '''QB 4.5 or lower''' versions. '''PDS(7.1) is not supported'''. The following sub-procedures have been created to do things that were available in '''PDS''' versions of '''QuickBASIC 7.0 and 7.1'''.


== CURRENCY ==

=== MKC$ ===
:* PDS could use the '''CURRENCY''' variable type and had the '''MKC$''' function to convert those values into 8 byte [[ASCII]] string values.
:* QB64 can convert [[_FLOAT]] currency amounts to strings using [[_MK$]] with [[_INTEGER64]] values:
{{CodeStart}}
{{Cl|SCREEN}} 12
{{Cl|DIM}} value {{Cl|AS}} {{Cl|_FLOAT}}
value = 12345678901234.6789 'any currency value with up to 4 decimal point places

{{Cl|_PRINTSTRING}} (1, 50), "[" + MKC$(value) + "]" 'show ASCII string value
{{Cl|END}}

'-----------------------------------------------
'converts currency amount to PDS currency string
'-----------------------------------------------
{{Cl|FUNCTION}} MKC$ (CurrVal {{Cl|AS}} {{Cl|_FLOAT}})
    {{Cl|DIM}} CVal {{Cl|AS}} {{Cl|_INTEGER64}}
    CVal = CurrVal * 10000
    MKC$ = {{Cl|_MK$}}({{Cl|_INTEGER64}}, CVal)
{{Cl|END FUNCTION}}
{{CodeEnd}}
;Note:The [[_FLOAT]] currency amount must be multiplied by 10000 before it is converted to the [[ASCII]] string value.
----

=== CVC ===
:* PDS also had the '''CVC''' function to convert '''MKC$''' currency string values back to currency amounts.
:* QB64 can use [[_CV]] with [[_INTEGER64]] to convert those 8 byte values back to [[_FLOAT]] currency values.
:** In this example the procedure gets the currency string from a file.
{{CodeStart}}
{{Cl|SCREEN}} 12
{{Cl|DIM}} currency {{Cl|AS}} {{Cl|STRING}} * 8
{{Cl|OPEN}} "currency.bin" {{Cl|FOR (file statement)|FOR}} {{Cl|BINARY}} {{Cl|AS}} #1 'binary file with MKC$ values created by PDS
{{Cl|GET}} #1, , currency
{{Cl|CLOSE}} #1

{{Cl|_PRINTSTRING}} (1, 10), "[" + currency + "]" 'show ASCII string value from file
{{Cl|_PRINTSTRING}} (1, 30), {{Cl|STR$}}(CVC##(currency))
{{Cl|END}}

'-----------------------------------------------------------
'converts currency string to a {{Cl|_FLOAT}} currency amount
'-----------------------------------------------------------
{{Cl|FUNCTION}} CVC## (CurrStr {{Cl|AS}} {{Cl|STRING}})
    {{Cl|DIM}} CV {{Cl|AS}} {{Cl|_INTEGER64}}
    CV = {{Cl|_CV}}({{Cl|_INTEGER64}}, CurrStr)
    CVC = CV / 10000
{{Cl|END FUNCTION}}
{{CodeEnd}}
;Note:The [[_FLOAT]] currency amount must be divided by 10000 to create up to 4 decimal point places.

=== PUT ===
:* Currency values can be [[PUT]] directly into [[BINARY]] or [[RANDOM]] files using an [[_INTEGER64]] variable value.
:** Remember to multiply the currency value by 10000 before putting to file.
{{CodeStart}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}

currency = 9876.543
curr = currency * 10000 'multiply currency value

{{Cl|OPEN}} "currency.bin" {{Cl|FOR (file statement)|FOR}} {{Cl|BINARY}} {{Cl|AS}} #1 'a binary file to hold PDS currency values
{{Cl|PUT}} #1, , curr
{{Cl|CLOSE}} #1
{{Cl|END}}
{{CodeEnd}}

=== GET ===
:* When currency values are [[PUT]] directly into a [[BINARY]] or [[RANDOM]] file, [[_INTEGER64]] can [[GET]] them directly.
:** Remember to divide the currency value by 10000 after getting from file.
{{CodeStart}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}
{{Cl|OPEN}} "currency.bin" {{Cl|FOR (file statement)|FOR}} {{Cl|BINARY}} {{Cl|AS}} #1 'any binary file holding PDS currency values
{{Cl|GET}} #1, , curr
{{Cl|CLOSE}} #1

currency = curr / 10000 ' use any floating decimal point type within currency range

{{Cl|PRINT}} currency
{{Cl|END}}
{{CodeEnd}}
;Note:The currency value can be any [[SINGLE]], [[DOUBLE]] or [[_FLOAT]] floating decimal point value that will hold the range of values.

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== DIR$ ==
;Attention:Not to be confused with QB64's [[_DIR$]] function.

:* This PDS(7.1) '''derived DIR$ function''' returns a filename or a list when more than one exist.
:* The file specification (''spec$'') can use a path and/or wildcards.
{{CodeStart}}
{{Cl|FOR...NEXT|FOR}} i = 1 {{Cl|TO}} 2
    {{Cl|PRINT}}
    {{Cl|LINE INPUT}} "Enter a file spec: ", spec$
    file$ = DIR$(spec$) 'use a file spec ONCE to find the last file name listed
    {{Cl|PRINT}} DIRCount%, file$, 'function can return the file count using {{Cl|SHARED}} variable
    {{Cl|IF...THEN|IF}} DIRCount% > 1 {{Cl|THEN}}
        DO
            K$ = {{Cl|INPUT$}}(1)
            file$ = DIR$("") 'use an empty string parameter to return a list of files!
            {{Cl|PRINT}} file$,
        {{Cl|LOOP}} {{Cl|UNTIL}} {{Cl|LEN}}(file$) = 0 'file list ends with an empty string
    {{Cl|END IF}}
{{Cl|NEXT}}
{{Cl|END}}

{{Cl|FUNCTION}} DIR$ (spec$)
    {{Cl|CONST}} TmpFile$ = "DIR$INF0.INF", ListMAX% = 500 'change maximum to suit your needs
    {{Cl|SHARED}} '''DIRCount% 'returns file count if desired. MAY conflict with user's existing code'''
    {{Cl|STATIC}} Ready%, Index%, DirList$()
    {{Cl|IF...THEN|IF}} {{Cl|NOT}} Ready% {{Cl|THEN}} {{Cl|REDIM}} DirList$(ListMAX%): Ready% = -1 '{{Cl|DIM}} array first use
    {{Cl|IF...THEN|IF}} spec$ > "" {{Cl|THEN}} 'get file names when a spec is given
        {{Cl|SHELL}} {{Cl|_HIDE}} "DIR " + spec$ + " /b > " + TmpFile$
        Index% = 0: DirList$(Index%) = "": ff% = {{Cl|FREEFILE}}
        {{Cl|OPEN}} TmpFile$ {{Cl|FOR...NEXT|FOR}} {{Cl|APPEND}} {{Cl|AS}} #ff%
        size& = {{Cl|LOF}}(ff%)
        {{Cl|CLOSE}} #ff%
        {{Cl|IF...THEN|IF}} size& = 0 {{Cl|THEN}} {{Cl|KILL}} TmpFile$: {{Cl|EXIT FUNCTION}}
        {{Cl|OPEN}} TmpFile$ {{Cl|FOR (file statement)|FOR}} {{Cl|INPUT (file mode)|INPUT}} {{Cl|AS}} #ff%
        {{Cl|DO...LOOP|DO}} {{Cl|WHILE}} {{Cl|NOT}} {{Cl|EOF}}(ff%) {{Cl|AND (boolean)|AND}} Index% < ListMAX%
            Index% = Index% + 1
            {{Cl|LINE INPUT (file statement)|LINE INPUT}} #ff%, DirList$(Index%)
        {{Cl|LOOP}}
        DIRCount% = Index% '{{Cl|SHARED}} variable can return the file count
        {{Cl|CLOSE}} #ff%
        {{Cl|KILL}} TmpFile$
    {{Cl|ELSE}} {{Cl|IF...THEN|IF}} Index% > 0 {{Cl|THEN}} Index% = Index% - 1 'no spec sends next file name
    {{Cl|END IF}}
    DIR$ = DirList$(Index%)
{{Cl|END FUNCTION}}
{{CodeEnd}}
{{small|Code by Ted Weissgerber}}
{{PreStart}}
'''Explanation'''
  The function will verify that a file exists (even if it is
  empty) by returning it's name or it returns an empty string
  if no file exists. It can return a list of file names by using
  an empty string parameter("") after sending a wildcard spec to
  get the first file name. The number of file names found is
  returned by using the SHARED variable, '''DIRCount%'''. Unlike
  the PDS DIR$ function, '''it MUST use an empty string parameter
  until QB64 supports optional parameters!''' The function does
  NOT delete empty files.
{{PreEnd}}

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