Powershell：尾部最后一行并删除

Question

How can I use powershell -tail param to remove the last line from a file?

The following line gets the last line, but , when I set the content to the file it just stores that last line and disregards the rest...

Get-content $file -tail 1.

Answer 1

You can't

Get-Content -Tail $N only reads the last $N lines, it doesn't remove anything.

Most efficient way is probably using the System.IO.File.ReadAllBytes() and WriteAllBytes() methods:

# Read all lines
$LinesInFile = [System.IO.File]::ReadAllLines($file)
# Write all lines, except for the last one, back to the file
[System.IO.File]::WriteAllLines($file,$LinesInFile[0..($LinesInFile.Count - 2)])
# Clean up
Remove-Variable -Name LinesInFile