Category : Dbase (Clipper, FoxBase, etc) Languages Source Code
Archive   : DBV121.ZIP
Filename : DBV.DOC

DBV-DBF View, Version 1.21 14-Jun-92


Simple viewer for taking quick looks inside dBASE-compatible .DBF files in
record and browse modes. Does single-field, scan-across searches. File
header info, including field definitions, can be displayed either in
interpreted (human-readable) format, or as hex bytes. Editing of fields in
both record and browse modes enabled by command-line switch. New: New
searches automatically start from the first record. The user may include
default start-up switches in a configuration file.

Contents:
=========
Disclaimer
Purpose
Display
Syntax
Switches
Configuration
Commands
Background

Disclaimer:
===========
DBF View (DBV) and this documentation are offered as is. The user bears the
entire risk of this software not performing as expected.

Purpose:
========
For taking quick looks into .DBF files without having to load a
full-featured database program.

By user request, field editing has been incorporated into the program
starting from Version 1.20. Editing is enabled by command-line switch (see
"Switches" below).

DBV is a generic .DBF file viewer/editor. As there are different types of
index files, these are ignored in searches and editing.

DBV is a free program.

Display:
========
The program displays either in color or "black-and-white" based on the video
mode at program start-up. However, if the user has a color graphics card,
but no color monitor, the display may be improved by using the DOS command
"MODE BW80". Conversely, color mode may be forced on by using "MODE CO80".

A command-line switch is also available to force black-and-white mode. See
"Switches" below.

EGA/43- and VGA/50-line modes are supported. At program start-up, an
attempt is made to detect the actual number of lines on the screen, up to a
maximum of 50, and to adjust the display accordingly.

Syntax:
=======

Usage: DBV [switches] [filespec]

If no extension is specified for "filespec", ".DBF" is assumed. If a valid
filename is specified unambiguously, the file is immediately displayed.
Either specifying "filespec" using wildcards, or specifying a drive or
directory name causes a scrollable directory window to pop up. Simply
typing the program name is the same as specifying "*.DBF".

Examples: DBV C: <- current directory of drive C:
DBV D:\ <- root of drive D:
DBV \DBASE\DATA <- data subdirectory of \DBASE

Switches:
=========
/BW Black-and-White mode. Provided as an alternative to using DOS's
"MODE BW80" command.

/E enable field Edit. Index files are ignored, and will have to be
maintained by the user.

/W start program in Wide (browse) mode.

Either '/' or '-' may be used to specify switches.

Entering an invalid switch causes the program to display a brief help screen
then exit.

Examples: DBV /h
DBV -?

Configuration:
==============
An optional configuration file containing user-selected default switches may
be created or edited with any editor or word processor which can save pure
ASCII text files. This file should be named "DBV.CFG" and placed in the
same directory from which DBV.EXE is loaded (DOS 3.0 and above).

Switches, including switch options, may either be separated by spaces or
placed on separate lines.

A sample DBV.CFG file is included in the distribution archive for DBV.
After extracting the contents of the distribution archive, DBV.CFG may be
deleted if DBV's defaults are satisfactory.

Commands:
=========
, or the letter 'I', will display overall information on the .DBF file.
Pressing a second time, or the letter 'H', will open up a window
showing how this information is represented on disk as hex bytes.

, or the letter 'F', will display general information on each field.
Pressing a second time, or the letter 'H', will open up a window
showing how this information is represented on disk as hex bytes.

, or the letter 'E', allows one to edit the current field. This option
is only available if the /E switch has been specified on the command line or
included in DBV.CFG (see "Configuration" below).

will toggle between Browse and Record modes.

, or the letter 'G', opens up an input window into which you can type
the (sequential) number of the record you wish to jump to.

, or the letter 'S', will allow a forward search for the input string.
This search is of the "scan-across" variety, i.e. the search will include
embedded strings. New searches start from the first record. Subsequent
searches on the same input string (by pressing to accept the
previous string) will start from after the current record.

, , or the letter 'Q', will quit the program.

The , , , and arrow-keys, possibly used in
conjunction with the key, will hopefully have the intuitive effects.

When in Browse mode, either or will move right one field
at a time. and will have the opposite effect. The
key, used in combination with the left- and right- arrow keys will
page left and right, respectively.

The letters 'P' (previous) and 'N' (next) are synonyms for the and
keys, respectively.

Background:
===========
I wrote DBV to test my understanding of .DBF file structure. A pre-release
version of DBV allowed field editing. I disabled this feature before the
first public release because I was inconvenienced by having to rebuild my
multi-field index files with my regular database program, after editing with
DBV.

A few users have requested that I add field editing to DBV. They don't seem
to mind having to maintain their own index files. Although I would have
preferred leaving DBV as a simple viewer, adding editing back was simple, as
I already had the required routines at hand. I've decided that, for now at
least, editing would be enabled only by specifying the appropriate switch.

--

Raymond T. Kaya
P. O. Box 1436
Honolulu, HI 96806

CompuServe: 71230,2500
GEnie : R.KAYA1