powershell - 如何让 powershell 函数返回一个对象并设置 $？ $假？

Question

我在 powershell 函数中有一些代码，如下所示:

try {
    Invoke-SomethingThatFails
}
catch [System.Exception] {
    Write-Error $_.Exception.Message;
    return New-Object Namespace.CustomErrorType -Property @{
        'Code' = "Fail";
        "Message" = $_.Exception.Message;
    }
}

现在唯一的问题是我还想设置 $?为 $false。这可能吗？

Answer 1

来自 Bruce Payettes PowerShell In Action (Second Edition) :

The $? variable will be true if the entire operation succeeded, and false otherwise. For example, if any of the operations wrote an error object, then $? will be set to false even if the error was discarded using redirection. This is an important point: it means that a script can determine whether an error occurred even if the error isn’t displayed.

PowerShell 运行时管理 $? 的值当错误对象写入管道时设置为 false。

更新 以下是如何将错误对象写入管道但不终止它(管道):

function New-Error {
    [CmdletBinding()]
    param()
    $MyErrorRecord = new-object System.Management.Automation.ErrorRecord `
        "", `
        "", `
        ([System.Management.Automation.ErrorCategory]::NotSpecified), `
        ""
    $PSCmdlet.WriteError($MyErrorRecord)
}

$Error.Clear()
Write-Host ('$? before is: ' + $?)
New-Error
Write-Host ('$? after is: ' + $?)

输出:

$? before is: True

New-Error : 
At C:\...\....ps1:14 char:10
+ New-Error <<<< 
    + CategoryInfo          : NotSpecified: (:String) [New-Error], Exception
    + FullyQualifiedErrorId : New-Error

$? after is: False