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complete
27-12-2005, 13:36
So far the code I have written can read and write to and from a file.

In other words, I have the
Line Input #FileNum...and the Write #FileNum...written.

But how do I handel a situation where the file has negative numbers to be read? I am able to output to a file a negative integer. But when I try to read it back I get an error.
I assume I will have to read each line of the file one by one into a string and then have it converted. What are the string conversion routines in VB? The line of code is written as

-1

I suppose I have to do some string manipulation to get it stored back as a negative integer.

Mike
27-12-2005, 14:18
http://www.chiefdelphi.com/forums/showthread.php?t=29944
Replace Delphi with your programming language of choice (minus PIC C)

This is not a general programming website. We are for the FIRST robotics competition.

Ryan M.
27-12-2005, 16:31
Although we can try to help. ;)

I don't know VB worth crap, so there could be an easier way, but I'd say that you could check if it begins with a '-,' strip it off if it does, convert the main part to a number, then multiply by -1.

IE, if you have "-5" in a file, you take off hte negative ("5"), convert it to a number (5), then multiply by -1 (-5).

Astronouth7303
27-12-2005, 17:28
If you're using the Write # (http://msdn.microsoft.com/library/en-us/vbenlr98/html/vastmWrite.asp) statement, you should use Input # (http://msdn.microsoft.com/library/en-us/vbenlr98/html/vastminput.asp), not Line Input # (http://msdn.microsoft.com/library/en-us/vbenlr98/html/vastminput.asp).

Otherwise, VB is very good about preserving data.

Timothy D. Ginn
27-12-2005, 19:24
I believe the string conversion routine you're looking for is:

val()

It'll convert a string to a number.

The opposite is:

str()

(which converts a number to a string).