how to delete previous lines written with filewriteline?

[SoyArcano]

My question is if for example i write these lines

FileWriteLine($hFileOpen, "Line 1")

FileWriteLine($hFileOpen, "Line 2")

FileWriteLine($hFileOpen, "Line 3")

 

can i after delete them?

[iamtheky]

you can use _FileWriteToLine to delete (i imagine through after readline loop or filereadtoarray function to get the line to delete).

Quote

If _FileWriteToLine() is called with $iOverWrite as 1 and $sText as "", it will delete the line.

 

Edited January 16, 2018 by iamtheky

[AspirinJunkie]

Or:

• calculate the sum of the StringLengths (+ the line breaks)
• set the position with FileSetPos and the calculated length sum directly ahead of the written lines.
• use FileSetEnd() to cut the file at this position (the part after the current position is deleted)

as an alternative to the length-calculation you can use FileReadLine by using a negative line number.
So for example if you do FileReadLine($hFileOpen, -4) the file pointer is standing at the end of the fourth last line.
If you now use FileSetEnd() the last three lines will get deleted.

Edited January 17, 2018 by AspirinJunkie

[Juvigy]

If you havent saved the file you can reopen it and they will be gone.

[KickStarter15]

Try:

#include <File.au3>

_FileWriteToLine(@ScriptDir & "\test.txt", 3, "my replacement for line 3", True)
_FileWriteToLine(@ScriptDir & "\test.txt", 3, "", False)

Or

#Include <Array.au3>
#include <File.au3>

$sFilePath = @ScriptDir & '\Files.log'
Local $hFileOpen = FileOpen($sFilePath, $FO_APPEND)
If $hFileOpen = -1 Then
    MsgBox($MB_SYSTEMMODAL, "", "An error occurred whilst writing the temporary file.")
    Return False
EndIf

FileWriteLine($hFileOpen, "Line 2")
FileWriteLine($hFileOpen, "Line 3" & @CRLF)
FileWriteLine($hFileOpen, "Line 4" & @CRLF)
FileWriteLine($hFileOpen, "Line 5")

$aFiles = FileReadToArray($sFilePath)
$content = FileRead($sFilePath)

MsgBox(0,"Test",$content)

; ===========================
; if you will commented this lines, it will not delete your inserted lines in text file
For $i = 0 to UBound($aFiles)-1
   $content = StringRegExpReplace($content, $aFiles[$i] & '\R?', "")
Next
$hFile = FileOpen($sFilePath, 2)
FileWrite($hFile, $content)
FileClose($hFile)
; ===========================