在 Powershell 中确定自定义对象的范围答案

【问题标题】：Scoping Custom Objects in Powershell在 Powershell 中确定自定义对象的范围
【发布时间】：2016-03-01 23:22:08
【问题描述】：

所以我有一个似乎应该很容易解决的 powershell 问题，但我自己却无法解决。

以下面的程序为例：

$MyFavoriteAnimals = @()
$Pets = "Cat","Dog","Fish","Bird"
$Names = "Jeb","Rex","Sam","Roger"

For ($i=0; $i -lt 4; $i++)
{
    $NewAnimal = @{"Kind" = $Pets[$i]; "Name" = $Names[$i]}
    $MyFavoriteAnimals += New-Object pscustomobject -Property $NewAnimal
}
$MyFavoriteAnimals | FT Kind, Name -AutoSize

这工作正常，并具有以下输出：

Kind Name 
---- ---- 
Cat  Jeb  
Dog  Rex  
Fish Sam  
Bird Roger

...但是如果我尝试将其放入一个函数并将 $MyFavoriteAnimals 作为全局范围，那么 New-Object 命令将停止工作：

Function My-Favorite-Animals {

    $Global:MyFavoriteAnimals = @()

    $Pets = "Cat","Dog","Fish","Bird"
    $Names = "Jeb","Rex","Sam","Roger"

    For ($i=0; $i -lt 4; $i++)
    {
        $NewAnimal = @{"Kind" = $Pets[$i]; "Name" = $Names[$i]}
        $MyFavoriteAnimals += New-Object pscustomobject -Property $NewAnimal
    }

}

My-Favorite-Animals
$MyFavoriteAnimals | FT Kind, Name -AutoSize

...我收到以下错误：

Method invocation failed because [System.Management.Automation.PSObject]     does not contain a method named 'op_Addition'.
At line:13 char:9
+         $MyFavoriteAnimals += New-Object pscustomobject -Property $NewAnimal
+         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo          : InvalidOperation: (op_Addition:String) [], RuntimeException
+ FullyQualifiedErrorId : MethodNotFound

【问题讨论】：

标签： powershell pscustomobject

【解决方案1】：

指定：**$Global:**MyFavoriteAnimals +=，如：

Function My-Favorite-Animals {

    $Global:MyFavoriteAnimals = @()

    $Pets = "Cat","Dog","Fish","Bird"
    $Names = "Jeb","Rex","Sam","Roger"

    For ($i=0; $i -lt 4; $i++)
    {
        $NewAnimal = @{"Kind" = $Pets[$i]; "Name" = $Names[$i]}
        $Global:MyFavoriteAnimals += New-Object pscustomobject -Property $NewAnimal
    }

}

My-Favorite-Animals
$MyFavoriteAnimals | FT Kind, Name -AutoSize

【讨论】：