open text file and read from last data first until first data

10-05-2005, 11:24 PM

jazmiey

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Join Date: Oct 2005

Posts: 10

open text file and read from last data first until first data

usually open file for read text file read from first data until last data right?
now i want to do is read last data first in text file until first data.

thank you

Last edited by italkid; 10-06-2005 at 01:18 AM. Reason: Removed offline help request (e-mail address).

10-06-2005, 12:02 AM

DJ_Klepc

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Location: Slovenia

Posts: 602

You can read text file normaly and then use StrReverse function which will reverse whole string so it will look like you read file from end to start.

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10-06-2005, 01:05 AM

jazmiey

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Join Date: Oct 2005

Posts: 10

for your information my system is i write serial no in text file and continues append writing to this file.when new serial no want to save to this file,the system must check it first is it already exist or not in this file.but it only check 50 serial no from the last data to up data.

inside this file not only serial no but also write time,serial no,and so on

the problem is how to read from the last data to first 50 data from last data?no need read first all the data.just until 50th from last data.

thank you

Quote:

Originally Posted by jazmiey

usually open file for read text file read from first data until last data right?
now i want to do is read last data first in text file until first data.

thank you

Last edited by italkid; 10-06-2005 at 01:18 AM.

10-06-2005, 01:56 AM

DJ_Klepc

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Join Date: Apr 2004

Location: Slovenia

Posts: 602

Oh that! Say So!

You can use binary access and go from last character to first, Character by character. Then store this characters together so you will get the text you need.

Code:

Open File for Binary as #1
for i= filelen to 1 Step -1
    get #1, i, character
    text=i & text
'    check if text is data you need and if it is then exit for
next i

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10-06-2005, 07:28 AM

loquin

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If there's a fixed number of bytes per entry, get the file length,subtract the (bytes-per-entry * 50) and read. Then, search.

Since you're validating the serial number every time, this would probably be a good use for a simple database storage, like Access. If you set a primary or unique key on the serial number, ADO wouldn't allow a duplicate entry.

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