PowerShell:
Читання текстового файлу
Як робити:
Читання всього файлу одразу:
$content = Get-Content -Path "D:\Example\file.txt"
Write-Host $contentSample output:
Це текст з файлу.
Ура!Читання файлу построково:
Get-Content -Path "D:\Example\file.txt" | ForEach-Object {
Write-Host $_
}Sample output:
Це текст з файлу.
Ура!Використання StreamReader для великих файлів:
$stream = [System.IO.StreamReader] "D:\Example\huge_file.txt"
while ($line = $stream.ReadLine()) {
Write-Host $line
}
$stream.Close()Поглиблено
Reading text files is fundamental in programming. In the DOS era, we had TYPE and MORE commands. PowerShell, more advanced, introduced Get-Content cmdlet, which is part of the Microsoft.PowerShell.Management module.
While Get-Content is handy for small-to-medium files, StreamReader (a .NET class) should be used for larger ones to save memory and improve performance. For instance, StreamReader reads a file lazily (line by line) when you loop through it, instead of loading the entire content into memory.
You can also use other .NET classes like File.ReadAllLines or File.ReadAllText when interoperating within different .NET languages, which further exemplifies the versatility in file handling within the PowerShell environment.
Alternatives within PowerShell include Import-Csv for structured data and Select-String for pattern matching, which both internally handle text file reading but with additional layers for their specific use-cases.