代码之家 › 专栏 › 技术社区 › yzorg

使用[Console]::ReadLine()时未收到通过管道传输到PowerShell.exe的文本

powershell command-line

yzorg · 技术社区 · 15 年前

调用.NET时,我的数据丢失了 [Console]::ReadLine() 读取到PowerShell.exe的管道输入。在CMD中,运行:

>ping localhost | powershell -NonInteractive -NoProfile -C "do {$line = [Console]::ReadLine(); ('' + (Get-Date -f 'HH:mm
:ss') + $line) | Write-Host; } while ($line -ne $null)"
23:56:45time<1ms
23:56:45
23:56:46time<1ms
23:56:46
23:56:47time<1ms
23:56:47
23:56:47

通常情况下,Vista64中的“ping localhost”看起来是这样的,因此上面的输出中缺少很多数据:

Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data:
Reply from ::1: time<1ms 
Reply from ::1: time<1ms 
Reply from ::1: time<1ms 
Reply from ::1: time<1ms 

Ping statistics for ::1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

namespace ConOutTime {
    class Program {
        static void Main (string[] args) {
            string s;
            while ((s = Console.ReadLine ()) != null) {
                if (s.Length > 0) // don't write time for empty lines
                    Console.WriteLine("{0:HH:mm:ss} {1}", DateTime.Now, s);
            } 
        }
    }
}

输出:

00:44:30 Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data:
00:44:30 Reply from ::1: time<1ms
00:44:31 Reply from ::1: time<1ms
00:44:32 Reply from ::1: time<1ms
00:44:33 Reply from ::1: time<1ms
00:44:33 Ping statistics for ::1:
00:44:33     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
00:44:33 Approximate round trip times in milli-seconds:
00:44:33     Minimum = 0ms, Maximum = 0ms, Average = 0ms

因此,如果从PowerShell而不是C调用相同的API,StdIn的许多部分都会被“吃掉”。即使我没有使用“PowerShell.exe-Command-”,PowerShell主机是否仍在从StdIn读取字符串?

3 回复 | 直到 8 年前

Joey Gumbo 15 年前

$input PowerShell中的枚举器,以访问通过管道传输到程序中的数据。我还发现 [Console]::ReadLine() 不知怎的,什么都没做。但原因不明。

C:\Users\Me> ping localhost | powershell -noninteractive -noprofile -c "$input|%{(date -f HH:mm:ss)+' '+$_}"

07:31:54
07:31:54 Pinging Sigmund [::1] with 32 bytes of data:
07:31:54 Reply from ::1: time<1ms
07:31:54 Reply from ::1: time<1ms
07:31:54 Reply from ::1: time<1ms
07:31:55 Reply from ::1: time<1ms
07:31:55
07:31:55 Ping statistics for ::1:
07:31:55     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
07:31:55 Approximate round trip times in milli-seconds:
07:31:55     Minimum = 0ms, Maximum = 0ms, Average = 0ms

C:\Users\Me>ping localhost

Pinging Sigmund [::1] with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

stej 15 年前

一个可能的解决方案是:

powershell -NonInteractive -NoProfile -C  "ping localhost | % { ('' + (Get-Date -f 'HH:mm:ss') + $_) | Write-Host; }"

我为其他问题访客添加它,因为我认为您不使用它有一些原因:)

yzorg 15 年前

我最终从PowerShell内部调用了外部工具,并将管道连接到Out Time advanced函数。。。

function Out-Time { 
param (
    [parameter(ValueFromPipeline=$true)]
    $Value, 
    [switch] $OutputEmptyLines=$false) 
process {
    if (!$OutputEmptyLines -and ($Value -eq $null -or $Value -eq '')) {
    } 
    else {
        "{0} {1}" -f @((get-date -Format "HH:mm:ss.ff"), $Value)
    }
} 
}
#test
#ping localhost | Out-Time; ping localhost | Out-Time -OutputEmpty