区别$？和PowerShell中的$ LastExitCode [英] Difference between $? and $LastExitCode in PowerShell

问题描述

在PowerShell中， $？和 $ LastExitCode 之间有什么区别？

我阅读了关于自动变量的，并说：

$？包含上次操作的执行状态。如果最后一个操作成功，它包含TRUE。如果失败，则包含FALSE。

$ LastExitCode包含最近运行的基于Windows的程序。

在 $

$ b

---

我问，因为我推测如果且仅当$ LastExitCode为0时， $？为True，但我发现了一个令人惊讶的反例： $ LastExitCode = 0，但在PowerShell中$？= False。

解决方案

$ LastExitCode 将stderr重定向到stdout会产生NativeCommandError code>是本机应用程序的返回代码。 $？只是返回 True 或 False 最后一个命令（cmdlet或native）退出时没有错误或没有。

对于cmdlet失败通常意味着异常，对于本机应用程序，它是一个非零退出代码：

  PS> cmd / cexit 5
 PS> $？ 
 False 
 PS> cmd / cexit 0
 PS> $？ 
 True 
         C 也会算作失败;对于本地应用程序，它取决于它们设置的退出代码。
 
In PowerShell, what is the difference between $? and $LastExitCode?

I read about automatic variables, and it said:

  
$?  Contains the execution status of the last operation. It contains TRUE if the last operation succeeded and FALSE if it failed.
  
  
$LastExitCode Contains the exit code of the last Windows-based program that was run.
In the definition of $? it doesn't explain what succeed and fail mean.



I ask because I presumed that $? is True if and only if $LastExitCode is 0, but I found a surprising counter-example: $LastExitCode=0 but $?=False in PowerShell. Redirecting stderr to stdout gives NativeCommandError.
解决方案
$LastExitCode is the return code of native applications. $? just returns True or False depending on whether the last command (cmdlet or native) exited without error or not. 

For cmdlets failure usually means an exception, for native applications it's a non-zero exit code:
PS> cmd /c "exit 5"
PS> $?
False
PS> cmd /c "exit 0"
PS> $?
True
Cancelling a cmdlet with Ctrl+C will also count as failure; for native applications it depends on what exit code they set.

                        
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