使用 powershell 复制新文件和更新文件

Question

当谈到 powershell 时，我是一个完全的新手，但是我得到了一个我需要改进的脚本，以便我们可以将更新的或新的文件从一个服务器移动到另一个服务器。我已经设法掌握了当前的脚本，但正在努力寻找正确的 cmdlet 和参数来实现所需的行为。

我的脚本成功地检测到更改的文件并将它们移动到准备传输到另一台服务器的位置，但它没有检测到任何新文件。

谁能给我一些关于如何实现这两种行为的指导？

$CurrentLocation = "C:\current"
$PreviousLocation = "C:\prev"
$DeltaLocation = "C:\delta"

$source = @{}

#
# Get the Current Location file information
#
Get-ChildItem -recurse $CurrentLocation | Foreach-Object {
    if ($_.PSIsContainer) { return }
    $source.Add($_.FullName.Replace($CurrentLocation, ""), $_.LastWriteTime.ToString())
}
Write-Host "Content of Source"
$source

$changesDelta = @{}
$changesPrevious = @{}

#
# Get the Previous Directory contents and compare the dates against the Current Directory contents 
#
Get-ChildItem -recurse $PreviousLocation | Foreach-Object {
    if ($_.PSIsContainer) { return }
    $File = $_.FullName.Replace($PreviousLocation, "")
    if ($source.ContainsKey($File)) {
        if ($source.Get_Item($File) -ne $_.LastWriteTime.ToString()) {
            $changesDelta.Add($CurrentLocation+$File, $DeltaLocation+$File)
            $changesPrevious.Add($CurrentLocation+$File, $PreviousLocation+$File)
        }
    }
}
Write-Host "Content of changesDelta:"
$changesDelta
Write-Host "Content of changesPrevious:"
$changesPrevious

#
# Copy the files into a temporary directory
#
foreach ($key in $changesDelta.Keys) {
    New-Item -ItemType File -Path $changesDelta.Get_Item($key) -Force
    Copy-Item $key $changesDelta.Get_Item($key) -Force
}
Write-Host $changesDelta.Count "Files copied to" $DeltaLocation

#
# Copy the files into the Previous Location to match the Current Location
#
foreach ($key in $changesPrevious.Keys) {
    Copy-Item $key $changesDelta.Get_Item($key) -Force
}

Answer 1

这是满足您需求的一种简化方法。需要注意的一点是，我使用的一些构造需要PSv3+。这不复制目录结构，只是复制文件。此外，它会比较可能会或可能不会做您想要的基本名称（忽略扩展名）。它可以通过使用.Name 而不是.BaseName 来扩展以包含扩展

#requires -Version 3

$CurrentLocation  = 'C:\current'
$PreviousLocation = 'C:\prev'
$DeltaLocation    = 'C:\delta'

$Current  = Get-ChildItem -LiteralPath $CurrentLocation -Recurse -File
$Previous = Get-ChildItem -LiteralPath $PreviousLocation -Recurse -File

ForEach ($File in $Current)
{
    If ($File.BaseName -in $Previous.BaseName)
    {
        If ($File.LastWriteTime -gt ($Previous | Where-Object { $_.BaseName -eq $File.BaseName }).LastWriteTime)
        {
            Write-Output "File has been updated: $($File.FullName)"
            Copy-Item -LiteralPath $File.FullName -Destination $DeltaLocation
        }
    }
    Else
    {
        Write-Output "New file detected: $($File.FullName)"
        Copy-Item -LiteralPath $File.FullName -Destination $DeltaLocation
    }
}

Copy-Item -Path "$DeltaLocation\*" -Destination $PreviousLocation -Force