Question

有人可以解释一下为什么在下面的例子中函数退出后，属性的更新没有被保留

function CreateConfigObject
{
    # base solution directory
    $Config = New-Object -typename PSObject

    # Build Config File Contents
    $Config | Add-Member -Name MyProperty -MemberType NoteProperty -Value "Original Value"

    return $Config
}

function MyFunction([ref]$obj)
{
    Write-Host "Inside function Before Updating : " $obj.Value
    Write-host "Are the objects equal? " $obj.Value.Equals($config.MyProperty)

    $obj.Value = "New Value"
    Write-Host "Inside function After Updating : " $obj.Value

}



$config = CreateConfigObject

Write-Host "Before calling function : " $config.MyProperty

MyFunction ([ref]$config.MyProperty)

Write-Host "After calling function : " $config.MyProperty

Answer 1

进行了一些计算，但我得到了答案。 [ref]将对象而不是值传递给函数。所以你需要做的是将$config传递给函数，然后引用它的值，以及该值的.MyProperty属性。看看这个略有改动的代码，看看我的观点：

function CreateConfigObject
{
    # base solution directory
    $Config = New-Object -typename PSObject

    # Build Config File Contents
    $Config | Add-Member -Name MyProperty -MemberType NoteProperty -Value "Original Value"

    return $Config
}

function MyFunction([ref]$obj)
{
    Write-Host "Inside function Before Updating : " $obj.value.MyProperty
    Write-host "Are the objects equal? " $obj.value.MyProperty.Equals($config.MyProperty)

    $obj.value.MyProperty = "New Value"
    Write-Host "Inside function After Updating : " $obj.value.MyProperty

}



$config = CreateConfigObject

Write-Host "Before calling function : " $config.MyProperty

MyFunction ([ref]$config)

Write-Host "After calling function : " $config.MyProperty

这将输出预期结果：

Before calling function :  Original Value
Inside function Before Updating :  Original Value
Are the objects equal?  True
Inside function After Updating :  New Value
After calling function :  New Value

当我在PowerShell中通过引用传递它时，为什么没有更新此属性

1 个答案: