解析 Powershell 变量

你们都给了我很大的帮助——让我首先这么说。

我从运行的函数中得到以下输出 - 数据存储在名为的变量中$response，从一个获得Invoke-RestMethod call.

@{ResourceType=UserStory; Id=202847; Name=Professional Lines: 2,800,000 Policy Aggregate Limit update}    

我如何将这些值解析为新变量，以便最终结果是

TP Id:202847 Professional Lines: 2,800,000 Policy Aggregate Limit update

你所展示的是字符串化的的形式自定义对象，它使用哈希表-like文本表示.

该自定义对象的定义如下所示：

# Construct a custom object with .ResourceType, .Id, and .Name properties.
$response = [pscustomobject] @{
  ResourceType = 'UserStory'
  Id = 202847
  Name = 'Professional Lines: 2,800,000 Policy Aggregate Limit update'
}

If you include this variable in an expandable string (interpolating string), you'll get the representation in your question^[1] - note that you'll get the same representation if you pass the object to the Write-Host cmdlet^[2], as well as even with default output formatting if [pscustomobject] instances are nested in property values:

# Note the enclosing "..."
PS> "$response"

@{ResourceType=UserStory; Id=202847; Name=Professional Lines: 2,800,000 Policy Aggregate Limit update}

# Custom object nested in a property value:
PS> [pscustomobject] @{ foo = [pscustomobject] @{ bar = 'baz' } }

foo
---
@{bar=baz}
 

请注意，如果没有包含"..."，借助 PowerShell 的输出格式化系统，您将获得更好的表格表示形式。

PS> $response  # direct output of the object

ResourceType     Id Name
------------     -- ----
UserStory    202847 Professional Lines: 2,800,000 Policy Aggregate Limit update

假设$response实际上仍然是一个自定义对象，而不是一个它的字符串表示，你可以简单地访问自定义对象的属性来构建字符串, again 使用一个可扩展字符串:

PS> "TP Id:$($response.Id) $($response.Name)"
TP Id:202847 Professional Lines: 2,800,000 Policy Aggregate Limit update

使用时需要注意$(...)围绕属性参考 - 请参阅这个答案有关 PowerShell 字符串扩展规则的摘要。

An 替代方法是使用-f操作员，它使用类似于 .NET 的格式化字符串String.Format() method:

PS> 'TP ID:{0} {1}' -f $response.Id, $response.Name
TP ID:202847 Professional Lines: 2,800,000 Policy Aggregate Limit update

^{[1] You can also obtain this representation by calling .psobject.ToString() on a custom object; curiously, just .ToString() doesn't work, as of PowerShell Core 6.1.0; this surprising discrepancy is discussed in this GitHub issue.}

^{[2] Do note that Write-Host's purpose is to provide for-display-only (to-host) output, which bypasses PowerShell's success output stream, and thereby the ability to capture or redirect its output - see this answer for more information.}