如何把PowerShell命令放入数组中？

Question

我有一个脚本，做一堆图像处理。到目前为止，它依次运行，只使用一个核心并且永远占用。我手边有四个核心。我想同时运行这些命令中的四个。要做到这一点，我需要把这些命令放在一个数组中。这些都是原来的命令：

convert.exe -density 200 -quality 80 -delete 0 -scene 1 C:\Users\mles\Desktop\ta2014\v33_1_21_Northland.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 22 C:\Users\mles\Desktop\ta2014\v33_22_31_Auckland.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 32 C:\Users\mles\Desktop\ta2014\v33_32_49_Waikato.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 50 C:\Users\mles\Desktop\ta2014\v33_50_62_Whanganui.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 63 C:\Users\mles\Desktop\ta2014\v33_63_69_Manawatu.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 70 C:\Users\mles\Desktop\ta2014\v33_70_75_Wellington.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 76 C:\Users\mles\Desktop\ta2014\v33_76_92_Marlborough.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 93 C:\Users\mles\Desktop\ta2014\v33_93_117_Canterbury.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 118 C:\Users\mles\Desktop\ta2014\v33_118_127_Otago.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 
convert.exe -density 200 -quality 80 -delete 0 -scene 128 C:\Users\mles\Desktop\ta2014\v33_128_141_Southland.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg 

到目前为止，我想出了这一点：

$array = @() 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 1 C:\Users\mles\Desktop\ta2014\v33_1_21_Northland.pdf C:\Users\mles\Desktop\ta2014\%03d_test.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 22 C:\Users\mles\Desktop\ta2014\v33_22_31_Auckland.pdf C:\Users\mles\Desktop\ta2014\%03d_test.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 32 C:\Users\mles\Desktop\ta2014\v33_32_49_Waikato.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 50 C:\Users\mles\Desktop\ta2014\v33_50_62_Whanganui.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 63 C:\Users\mles\Desktop\ta2014\v33_63_69_Manawatu.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 70 C:\Users\mles\Desktop\ta2014\v33_70_75_Wellington.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 76 C:\Users\mles\Desktop\ta2014\v33_76_92_Marlborough.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 93 C:\Users\mles\Desktop\ta2014\v33_93_117_Canterbury.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 118 C:\Users\mles\Desktop\ta2014\v33_118_127_Otago.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 
$array += "convert.exe -density 200 -quality 80 -delete 0 -scene 128 C:\Users\mles\Desktop\ta2014\v33_128_141_Southland.pdf C:\Users\mles\Desktop\ta2014\%03d.jpg" 

foreach ($element in $array) { 
    $MaxThreads = 4 
    While (@(Get-Job | Where { $_.State -eq "Running" }).Count -ge $MaxThreads) 
    { Write-Host "Waiting for open thread...($MaxThreads Maximum)" 
     Start-Sleep -Seconds 1 
    } 

    Start-Job -Scriptblock{ $element } 
} 

While (@(Get-Job | Where { $_.State -eq "Running" }).Count -ne 0) 
{ Write-Host "Waiting for background jobs..." 
    Get-Job #Just showing all the jobs 
    Start-Sleep -Seconds 1 
} 

ForEach ($Job in (Get-Job)) { 
    Remove-Job $Job 
} 

的工作开始，但立即退出。我想这与我如何在数组中存储命令有关？

Answer 1

您可能想看看workflows，但它们会碰到最多5个并发进程。还有几个使用运行空间池和PowerShell实现多线程的例子，这种方式绕过了这个限制。我给出了一个工作示例here。

或者只是将脚本块作为脚本块存储在数组中而不是字符串。

$commands = @() 
$commands += {echo "test1"} 
$commands += {echo "test2"} 
$commands += {echo "test3"} 
foreach($command in $commands){ 
    start-job $command 
}