Reading Data File, Need Hex Values

Ron

I need a way to read the hex values of an old DBase3 data file.

Can anyone give me some info regarding how to grab hex values out of a file?
Not sure exactly how to do this.

Thanks for your help.

Nov 15 '05 #1

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2210

Jon Skeet

Ron <ro*@razorvisio n.net> wrote:

I need a way to read the hex values of an old DBase3 data file.

Can anyone give me some info regarding how to grab hex values
out of a file?

What *exactly* do you mean by "the hex values"? I would expect a
database such as DBase3 to have a fairly complicated format... do you
have information about it?

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

Nov 15 '05 #2

Ron

I need to view/modify the hex code of the file. DBase3 isn't very
complicated, I have a map of the byte sequences and what they mean, I just
need to get at the numbers so I can parse it and make a few changes.

Here is a the DBase3 key:

Byte Description
0 03h, version number
1-3 Last update, YY, MM, DD
4-7 number of records, 32 bit integer
8-9 length of the header structure, 16 bit integer
10-11 length of a record, 16 bit integer
12-31 reserved
32-N Field Descriptors
This is an array of 32-byte descriptors, one for each field in the
record, up to 128 fields.
Byte Description
0-10 Field Name (padded with nul)
11 Field Type
C Character
N Numeric (-.0123456789)
L Logical (YyNnTtFf) (? if not initialized)
D Date (YYYYMMDD)
M memo
12-15 reserved
16 Field Length
17-31 reserved
N+1 0Dh field terminator
So if anyone can tell me how to open a file and read the hex values therein
I would be very appreciative.

Thanks for your input,

Ron

"Jon Skeet" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@news.microsof t.com...

Ron <ro*@razorvisio n.net> wrote:
I need a way to read the hex values of an old DBase3 data file.

Can anyone give me some info regarding how to grab hex values
out of a file?

What *exactly* do you mean by "the hex values"? I would expect a
database such as DBase3 to have a fairly complicated format... do you
have information about it?

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

Nov 15 '05 #3

Jon Skeet

Ron <ro*@razorvisio n.net> wrote:

I need to view/modify the hex code of the file. DBase3 isn't very
complicated, I have a map of the byte sequences and what they mean, I just
need to get at the numbers so I can parse it and make a few changes.

In that case I suggest you just use a BinaryReader - or even just a
Stream, where you can read the bytes directly.

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet/
If replying to the group, please do not mail me too

Nov 15 '05 #4

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