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jorgeng

Empty file

16 posts in this topic

I have opened a file with fileopen.

What is the easiest autoit command to empty file without needing to delete/create the file?

:idea:

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I have opened a file with fileopen.

What is the easiest autoit command to empty file without needing to delete/create the file?

:idea:

FileOpen() with the right parameter?

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FileOpen() with the right parameter?

Yes, i have done fileopen, fileread and get the value.

The value is Trade in one row. I want to replace it with NoTrade on one row, meaning

doing a rewrite with new value.

:idea:

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I think what Jos meant was this:

help on FileOpen():

Parameters:

...

[mode]: [optional] Mode to open the file in

...

2 = Write mode (erase previous contents)

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#5 ·  Posted (edited)

I think what Jos meant was this:

help on FileOpen():

Parameters:

...

[mode]: [optional] Mode to open the file in

...

2 = Write mode (erase previous contents)

So if i first do a fileopen 0 and fileread, can i depending on the result doing

a fileopen 2 which emptying the file, and then fileopen 1, filewrite with new data?

:idea:

Edited by jorgeng

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So if i first do a fileopen 0 and fileread, can i depending on the result doing

a fileopen 2 which emptying the file, and then fileopen 1, filewrite with new data?

:idea:

almost..

1. FileOpen with mode=0

2. FileRead

3. FileClose

4. FileOpen with mode=2

5. FileWrite

6. FileClose

No need to fileopen with mode= 1 to write the data as mode=2 is alreay write mode. And always remember to close your file handles.

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almost..

1. FileOpen with mode=0

2. FileRead

3. FileClose

4. FileOpen with mode=2

5. FileWrite

6. FileClose

No need to fileopen with mode= 1 to write the data as mode=2 is alreay write mode. And always remember to close your file handles.

Better yet, You don't need to open a file for reading

$sStr = FileRead("somefile")


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I like to always FileOpen, FileClose. Otherwite I'm sure I'll start forgetting to properly close open files

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I like to always FileOpen, FileClose. Otherwite I'm sure I'll start forgetting to properly close open files

I'm just pointing out that it doesn't have to be opened in any mode to read it. If he wants to read from the file the FileRead() does that without opening it at all. If he wants to empty the file contents then it should be

$hFile = FileOpen("somefile.txt", 2);; handles are best here

FileWrite($hFile, "")

FileClose($hFile)

And to replace the contents

$hFile = FileOpen("somefile.txt", 2);; handles are best here

FileWrite($hFile, "Some new string")

FileClose($hFile)

Remember, a file can be open for reading and writing at the same time.


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Remember, a file can be open for reading and writing at the same time.

How would that be done? Nested fileopens don't work for me and mode 0+1 just results in write mode (obviously).

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#11 ·  Posted (edited)

Hi,

you can read in a file, which is open in write mode, can't you?

But you can't write to file, which is open in read mode....

;-))

Stefan

Edited by 99ojo

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I've tried allot of combinations, but I can't seem to do it. There is no need for me to open a file in read/write mode anyways.

I think the OP's question is answered and I'm just streching this topic now though. :idea:

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#14 ·  Posted (edited)

Hi,

Sorry correction:

You have to use FileOpen (..., 0) to use FileRead or FileReadLine with an file handle.

See helpfile:

Failure: Sets @error to 1 if file not opened in read mode or other error.

Feeling like..... :idea:

;-))

Stefan

BTW @JohnOne: You are using a filehandle without a FileOpen -> $file isn't declared

Edited by 99ojo

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Not if $file contains a string path to the file, an open and close is auto performed.

Also its nice if your file contains more lines than one and you only need to work with one of them, just use FileReadLine($file,$line)


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I would use

#Include <File.au3>

$var = Fileread($file)
_FileWriteToLine($file,$line,$text,1) ;write line overwriting the existing line

I tried this and it works, and does what i want.

I have contracted a company building a php script on server and i had problem whith the delete

file which crashed the script since php wanted access to file too. I think this is a great way

to update a single line in a file without needing to open file, check status and so on since

in my case this can happens on the same second from many scripts.

Thanks.

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