Powershell中泛型类型的通用类型

Question

Powershel的仿制药非常令人困惑.要实例化一个简单的列表,你需要用手鼓跳舞:

$type = ("System.Collections.Generic.List"+'`'+"1") -as "Type"
$type= $type.MakeGenericType("System.string" -as "Type")
$o = [Activator]::CreateInstance($type)

但是,如果我需要更复杂的东西<Dictionary<string,List<Foo>>,例如:

或者例如这里: Dictionary<string,List<string>>

$listType = ("System.Collections.Generic.List"+'`'+"1") -as "Type"
$listType = $listType.MakeGenericType("System.string" -as "Type")
$L = [Activator]::CreateInstance($listType)

$dicType = ("System.Collections.Generic.Dictionary"+'`'+"2") -as "Type"

#the next line is problematic
$dicType = $dicType.MakeGenericType( 
     @( ("system.string" -as "Type"), 
        ("System.Collections.Generic.List" as "Type)) # and that's of course wrong
      )

$D = [Activator]::CreateInstance($dicType )

Answer 1

虽然你可以深入到CLR内部表示,使生活困难的自己,你不要有到:

$dict = new-object 'collections.generic.dictionary[string,int]'
$dict.add("answer", 42)

想要一个类型的文字表示？

[collections.generic.dictonary[string,int]]

完成.泛型类型参数怎么样？

$dictOfList = new-object 'collections.generic.dictionary[string,
    [collections.generic.list[int]]]'

完成.

但是,有一个不幸的问题.在PowerShell 2.0中,将BCL和第三方类型混合并匹配为类型参数时会出现错误.后者需要装配合格:

# broken over two lines for clarity with backtick escape
$o = new-object ('collections.generic.dictionary[[{0}],[{1}]]' -f `
        [type1].fullname, [type2].fullname)

希望这可以帮助.在PowerShell 3.0中,这已得到修复.