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75 lines
2.8 KiB
Markdown
75 lines
2.8 KiB
Markdown
The **SHARED** statement allows variables to be passed automatically to any [SUB](SUB) or [FUNCTION](FUNCTION) procedure.
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## Syntax
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> DIM SHARED Qt AS STRING * 1
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> DIM SHARED AS STRING * 1 Qt
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* [DIM](DIM)ensioned variables are shared with all procedures in the program module.
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* When used with [DIM](DIM) in the main module, it eliminates the need to pass a parameter variable to a [SUB](SUB) or [FUNCTION](FUNCTION).
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* Use [COMMON SHARED](COMMON-SHARED) to share a list of variable values with sub-procedures or other modules. See also: [COMMON](COMMON)
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* SHARED (**without [DIM](DIM)**) can share a list of variables inside of [SUB](SUB) or [FUNCTION](FUNCTION) procedures with the main module only.
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* When using the **AS type variable-list** syntax, type symbols cannot be used.
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> **Note: SHARED variables in sub-procedures will not be passed to other sub-procedures, only the main module.**
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## Example(s)
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Defining variable types with [AS](AS) or type suffixes.
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```vb
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DIM SHARED Qt AS STRING * 1, price AS DOUBLE, ID AS INTEGER
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DIM SHARED Q$, prices#, IDs%
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```
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The DIR$ function returns a filename or a list when more than one exist. The file spec can use a path and/or wildcards.
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```vb
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FOR i = 1 TO 2
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LINE INPUT "Enter a file spec: ", spec$
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file$ = DIR$(spec$) 'use a file spec ONCE to find the last file name listed
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PRINT DIRCount%, file$, 'function can return the file count using SHARED variable
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DO
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K$ = INPUT$(1)
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file$ = DIR$("") 'use an empty string parameter to return a list of files!
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PRINT file$,
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LOOP UNTIL LEN(file$) = 0 'file list ends with an empty string
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NEXT
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END
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FUNCTION DIR$ (spec$)
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CONST TmpFile$ = "DIR$INF0.INF", ListMAX% = 500 'change maximum to suit your needs
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SHARED DIRCount% 'returns file count if desired
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STATIC Ready%, Index%, DirList$()
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IF NOT Ready% THEN REDIM DirList$(ListMax%): Ready% = -1 'DIM array first use
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IF spec$ > "" THEN 'get file names when a spec is given
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SHELL _HIDE "DIR " + spec$ + " /b > " + TmpFile$
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Index% = 0: DirList$(Index%) = "": ff% = FREEFILE
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OPEN TmpFile$ FOR APPEND AS #ff%
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size& = LOF(ff%)
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CLOSE #ff%
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IF size& = 0 THEN KILL TmpFile$: EXIT FUNCTION
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OPEN TmpFile$ FOR INPUT AS #ff%
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DO WHILE NOT EOF(ff%) AND Index% < ListMAX%
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Index% = Index% + 1
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LINE INPUT #ff%, DirList$(Index%)
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LOOP
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DIRCount% = Index% 'SHARED variable can return the file count
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CLOSE #ff%
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KILL TmpFile$
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ELSE IF Index% > 0 THEN Index% = Index% - 1 'no spec sends next file name
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END IF
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DIR$ = DirList$(Index%)
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END FUNCTION
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```
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> *Explanation:* The SHARED variable value *DIRcount%* can tell the main program how many files were found using a wildcard spec.
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## See Also
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* [DIM](DIM), [REDIM](REDIM)
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* [COMMON](COMMON), [COMMON SHARED](COMMON-SHARED)
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