PowerShell 3.0应该有更清晰的语法，它看起来像什么？

Question

我见过提到的改进的PowerShell 3.0语法，但没有一个例子，它将如何看起来像？

Answer 1

Powershell已经有一个非常干净的语法，所以没有太多需要改进。

一个新此外，我做喜欢的是Hash Table as objects，在那里你可以通过hastable与它的属性创建对象：

[<ClassName>]$Variable = @{<Property>=<Value>;<Property>=<Value>} 

所以创建自定义对象的更新，更简洁的方式是：

$obj = [PSCustomObject]@{a=1; b=2; c=3; d=4} 

重定向已经加强。除了正常（流水线）和错误外，现在您还可以进行冗余，调试和警告，因此您可以执行重定向，如5>&1

您可以使用$PSDefaultParameterValues首选变量为cmdlet设置默认参数值。

有新[ordered]加速器创建有序hastable（字典）：

$a = [ordered]@{a=1;b=2;d=3;c=4} 

从这里SO另一个答案，我意识到，-in在PowerShell中3.0是新的：

所以你做一些像1 -in 1,2,3。以前我们只有-contains

的cmdlet：

您可以Update-Help cmdlet的更新的帮助。有与网络相关的cmdlet，如Invoke- WebRequest。您还可以使用ConverTo-JSON和ConvertFrom-JSON cmdlet处理JSON。

Answer 2

下面是一个例子：

dir | where length -lt 10

3.0之前，它会一直

dir | where {$_.length -lt 10}

编辑：另一个例子，这次用foreach对象

dir | foreach-object length

Answer 3

许多常见的*-Object cmdlet都使用多个参数集来完成简化的语法。看看这个在V3：

C:\PS> Get-Command Where-Object -Syntax 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] [-EQ] [<CommonParameters>] 

Where-Object [-FilterScript] <scriptblock> [-InputObject <psobject>] [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CGT [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CNE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -LT [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CEQ [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -NE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -GT [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CLT [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -GE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CGE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -LE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CLE [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -Like [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CLike [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -NotLike [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CNotLike [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -Match [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CMatch [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -NotMatch [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CNotMatch [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -Contains [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CContains [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -NotContains [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CNotContains [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -In [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CIn [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -NotIn [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -CNotIn [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -Is [<CommonParameters>] 

Where-Object [-Property] <string> [[-Value] <Object>] [-InputObject <psobject>] -IsNot [<CommonParameters>] 

注意：检查出新的运营商-NotIn和-In如：

C:\PS> 1 -In 1..5 
C:\PS> 10 -NotIn 1..5 

所以简化语法是“共同”的情况下很好，但看出来的你可以很容易地掉入锋利的岩石和熔岩中，例如：

C:\PS> Get-ChildItem | Where LastWriteTime.Year -eq 2010 

这将返回什么更糟糕的，没有错误，所以你想结果集是“正确”的空当，其实这句法只是不为你所期望的工作。也就是说，您无法访问属性的属性。在上面，PowerShell寻找一个名为LastWriteTime.Year的属性，该属性不存在。

另请注意，作为简化语法的一部分，您现在可以使用$PSItem代替$_，以防您或您编写脚本的人对$_产生某种过敏反应。 :-)

虽然这不一定是联系在一起的简化的语法我发现，它简化了我的生活，我喜欢它：

C:\PS> Get-ChildItem -Directory 
C:\PS> Get-ChildItem -File 
C:\PS> dir -ad 
C:\PS> Get-ChildItem -Attributes System+Hidden+Directory+!Archive