64 lines
2.6 KiB
HTML
64 lines
2.6 KiB
HTML
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<HTML>
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<HEAD><TITLE>QuickBASIC 3.0 - Long Entry</TITLE></HEAD>
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<BODY>
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<A HREF="ng10e75.html">[<<Previous Entry]</A>
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<A HREF="ng320.html">[^^Up^^]</A>
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<A HREF="ng11727.html">[Next Entry>>]</A>
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<A HREF="menu.html" >[Menu]</A>
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<A HREF="info.html">[About The Guide]</A>
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<HR>
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<PRE>
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<B>FIELD Allocate Space for Random File Variables</B>
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<B>FIELD</B> [#]<U>filenum</U>, <U>fieldwidth</U> <B>AS</B> <U>stringvar</U> [,<U>fieldwidth</U> AS <U>stringvar</U>]...
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Allocates storage for any number of string variables, each of
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specified character width, to be used in conjunction with a specified
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random file buffer.
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<U>filenum</U> The number under which the file was OPENed.
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<U>fieldwidth</U> The number of character positions to be allotted to
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<U>stringvar</U>.
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<U>stringvar</U> A string variable to be used for random access.
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----------------------------------------------------------------------
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<B>Notes:</B> Once the random file has been FIELDed, data may be
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extracted from the random file buffer after a GET
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statement or placed into the buffer in preparation for a
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PUT statement.
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A string variable defined by means of the FIELD statement
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points to a specified position in the random file buffer.
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It should not thereafter be used as an INPUT variable or
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on the left side of an assignment statement. Doing either
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of these things will point the variable name into the
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string space and remove it from the file buffer.
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Multiple field definitions for a given random file buffer
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are permitted. Each new FIELD statement starts again at
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the first character position of the buffer, and all FIELD
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statements for a given random file are in effect
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simultaneously. All FIELD definitions are removed when a
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file is CLOSEd.
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QuickBASIC resets all FIELDed variables to null when the
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associated file is CLOSEd or RESET. (In interpreted BASIC,
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such variables retain their last assigned values.)
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</PRE>
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<HR>
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<B>See Also:</B>
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<A HREF="ng127c8.html">GET (File I/O)</A>
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<A HREF="ng1b48a.html">LSET</A>
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<A HREF="ng298af.html">PUT (File I/O)</A>
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<A HREF="ng2bce4.html">RSET</A>
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<HR>
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This page created by ng2html v1.05, the Norton guide to HTML conversion utility.
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Written by <A HREF="http://www.acemake.com/hagbard">Dave Pearson</A>
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<HR>
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</BODY>
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</HTML>
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