如何在powershell中选择具有特殊字符的键？

Question

我有一组来自JSON文件的键/值对。

$ $p.dependencies

@architect/architect : ^5.7.0
@architect/functions : ^3.0.4
assert               : ^1.4.1
bcrypt               : ^3.0.6
find-parent-dir      : ^0.3.0
hashids              : ^1.2.2
http-status-codes    : ^1.3.2
lodash.get           : ^4.4.2
mini-web-server      : ^1.0.2
mini-webhook-server  : ^1.0.4
mocha                : ^5.2.0
opencorporates       : ^3.0.0
stripe               : ^6.23.1
uuid                 : ^3.3.2
whois-json           : ^2.0.4

在Powershell中，它们是noteProperty的：

   TypeName: System.Management.Automation.PSCustomObject
Name                 MemberType   Definition
----                 ----------   ----------
Equals               Method       bool Equals(System.Object obj)
GetHashCode          Method       int GetHashCode()
GetType              Method       type GetType()
ToString             Method       string ToString()
@architect/architect NoteProperty string @architect/architect=^5.7.0
@architect/functions NoteProperty string @architect/functions=^3.0.4
assert               NoteProperty string assert=^1.4.1
bcrypt               NoteProperty string bcrypt=^3.0.6
find-parent-dir      NoteProperty string find-parent-dir=^0.3.0
hashids              NoteProperty string hashids=^1.2.2
http-status-codes    NoteProperty string http-status-codes=^1.3.2
lodash.get           NoteProperty string lodash.get=^4.4.2
mini-web-server      NoteProperty string mini-web-server=^1.0.2
mini-webhook-server  NoteProperty string mini-webhook-server=^1.0.4
mocha                NoteProperty string mocha=^5.2.0
opencorporates       NoteProperty string opencorporates=^3.0.0
stripe               NoteProperty string stripe=^6.23.1
uuid                 NoteProperty string uuid=^3.3.2
whois-json           NoteProperty string whois-json=^2.0.4

我想用@architect/functions ^3.0.4 键将项更改为与^3.0.4(然后将数据保存回来)不同的值

接下来的部分似乎是从哈希表中选择正确的项。我正在使用：

$p.dependencies | where $_.key -eq "@architect/functions"

但是，这不会返回任何结果。如何选择带有键@architect/functions**?**的项目作为积分，如何更改值！

编辑：

使用这个答案，这是我的最后一个脚本，如果有人觉得有用的话。

ls 'src/http' | foreach { 
    $packageJSONFile = "${PSItem}\package.json" 
    $packageJSON = cat $packageJSONFile | convertfrom-json
    if ( $packageJSON.dependencies.'@architect/functions'  ) {
        $packageJSON.dependencies.'@architect/functions' = '^3.0.4'
    }   
    $packageJSON | ConvertTo-Json -depth 100| set-content $packageJSONFile
} 

Answer 1

若要获取名称中具有特殊字符的属性，请引用该属性：

$p.dependencies.'@architect/functions'

Answer 2

Tomalak's helpful answer解决了你的问题。

至于您试图使用where (Where-Object)检索感兴趣的属性：

$p.dependencies | where $_.key -eq "@architect/functions"

有两个基本问题：

• 在摘要中，使用比较语句语法(即使用单个参数而不是脚本块)要求您单独使用属性名称(key)，而不是通过自动变量$_ ($_.key)。

- In fact, `$_` - to refer to the pipeline input object at hand - is only ever meaningful _inside a script block_ (`{ ... }`).
- That is, if your command were otherwise correct (it isn't, see below), you'd have to use:

$p.dependencies | where key -eq '@architect/functions'

​

• 如您的输出所示，$p.dependencies包含一个[pscustomobject]实例，而不是哈希表([hashtable])；ConvertFrom-Json返回[pscustomobject]实例，除非您使用-AsHashtable开关显式请求哈希表。

- If it were a hash table, PowerShell would send it through the pipeline _as a whole_.
- In order to send a hash table's _entries_ one by one through the pipeline, you'd have to call `.GetEnumerator()` on it, which would allow you to filter by their `Key` property.

​