Know when last line of file is reached

[Phaser]

Hi Guys

I am currently trying to use data from a text file, currently I have a counter to increment to the next line when I call it next

$zap = FileReadLine($datafile, $linecounter)

I know its best NOT to increment this way BUT I am calling line 1, using the data then calling line 2 using the data etc etc

Each file is different in length so I can't stop it as I don't know when the counter grabs the last line.

So, my question is, how do I know when it's at the last line so I can stop the program? I've tried @error = -1 but as I am not within a loop until I get the end of the file, I just call each line when I need it, any ideas?

Many thanks as always

[iamtheky]

#include <file.au3>

$max = _filecountlines($datafile)

for $linecounter = 1 to $max
$zap = FileReadLine($datafile, $linecounter)
;whatever you are doing with $zap
next

Edited November 30, 2012 by boththose

[BrewManNH]

Hi Guys

I am currently trying to use data from a text file, currently I have a counter to increment to the next line when I call it next

$zap = FileReadLine($datafile, $linecounter)

I know its best NOT to increment this way BUT I am calling line 1, using the data then calling line 2 using the data etc etc

Doing it this way isn't necessary, regardless of what you're doing with the information from the line. If you use FileOpen before you read the first line, and use the file handle returned from the FileOpen, the next line read will always be the just after the previously read line.

Each file is different in length so I can't stop it as I don't know when the counter grabs the last line.

So, my question is, how do I know when it's at the last line so I can stop the program? I've tried @error = -1 but as I am not within a loop until I get the end of the file, I just call each line when I need it, any ideas?

You need to check for the error immediately after reading the line from the file, or store the error message returned in a variable and read the variable later.

$hFile = FileOpen("YourTextFile.txt")
$Text = FileReadLine($hFile) ; reads the first line of the file
If @error = -1 Then _FunctionThatHappensAfterTheEndOfFileIsReached()

; do something here

$Text = FileReadLine($hFile) ; reads the second line of the file

; do something else here

$Text = FileReadLine($hFile) ; reads the third line of the file
Func _FunctionThatHappensAfterTheEndOfFileIsReached()
    Exit
EndFunc

[Phaser]

Thanks very much boththose, simple really, didn't know that function was available, I don't see it in the help file.

[jchd]

#include <file.au3>

$max = _filecountlines($datafile)

for $linecounter = 1 to $max
$zap = FileReadLine($datafile, $linecounter)
;whatever you are doing with $zap
next

That's the absolute worst way to do it: you read the file twice, decomposing it in lines each time.

_FileReadToArray unless the file is too large for memory (unlikely in most cases).