# ... 变量初始化已省略
$subscriptions | ForEach-Object {
    Select-AzSubscription -Subscription $_.Name
    $vms = Get-AzVm -Status | Where-Object {$_.StorageProfile.OsDisk.OsType -eq "Windows" -and $_.Name -notlike "azbecdns*" -and $_.Name -notlike "SF160SV0*" -and $_.PowerState -eq "VM running";}
    forEach ($vm in $vms) {
        $CSEvalidation = Get-AzVmExtension -VmName $vm.name -ResourceGroupName $vm.resourceGroupName | where-object {$_.Extensiontype -like "CustomScript*"} 
        if ($CSEvalidation -ne $null)
        {
            Remove-AzVmExtension -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -Name $CSEvalidation.name -Force -ErrorAction Continue
        }
        Set-AzVMCustomScriptExtension -TypeHandlerVersion 1.10 `
                -ResourceGroupName $vm.resourceGroupName `
                -VMName $vm.Name `
                -FileName $fileName `
                -ContainerName $containerName `
                -StorageAccountName $storageAccountName `
                -StorageAccountKey $storageAccountKey `
                -Run $fileName `
                -Location "West Europe" `
                -Name "CustomScriptExtension"
        # 这个变量解析有效，并列出所有虚拟机
        $cseOutput = "test"
        # 这不起作用，只列出了最初的最后一个虚拟机实例
        $cseOutput = ((Get-AzVm -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -Status).Extensions | Where {$_.Type -eq 'Microsoft.Compute.CustomScriptExtension'}).SubStatuses.Message[0]
        [PSCustomObject] @{
            VmName = $vm.name
            AgentVer = $cseOutput
        }
    }
} | Select-Object -Property VmName, AgentVer | Where-Object {$_.VmName -ne $null} | export-csv -NoTypeInformation -delimiter ';' -Path $(Pipeline.Workspace)\***.csv

**更新**：
* `$cseOutput` 的值中存在*隐藏控制字符*，导致了问题，通过使用 `$cseOutput = $cseOutput -replace ''\W''` 将其消除解决了问题。
  * 请注意，这个特定的基于正则表达式的 [`-replace`](https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_Comparison_Operators#replacement-operator) 操作会从字符串中移除所有不是_单词_字符的字符，即不是字母数字字符或 `_` 的任何字符。
  * 要限制移除仅限于_控制字符_和_隐藏格式字符_（参见[正则表达式中的字符类](https://docs.microsoft.com/en-us/dotnet/standard/base-types/character-classes-in-regular-expressions#SupportedUnicodeGeneralCategories)），请使用：  
    `$cseOutput = $cseOutput -replace ''[\p{Cc}\p{Cf}]''`
---
#### 原始答案：
您的症状有点神秘：如果哈希表中有多个条目，您*应该*看到多行，尽管列名是固定的 `"Name","Key","Value"`；尝试使用 `@{ one = 1; two = 2; three = 3 }.GetEnumerator() | ConvertTo-Csv` 作为一个快速示例。
---
> 我应该如何修改脚本以获得我想要的结果 - 一个包含所有订阅的所有虚拟机名称和 cse 子状态消息的 CSV 文件。
注意：**问题已更新，包含以下代码，并进行了修改。**
在您的 `foreach` 循环中，发出具有所需 CSV 列名的属性的 `[pscustomobject]` 实例，让 PowerShell 将它们收集到一个数组中 - 或者更好地，切换到 `ForEach-Object` 并将这些对象直接管道到 `Export-Csv`：
```shell
# ... 变量初始化省略
$subscriptions |
  ForEach-Object {
    Select-AzSubscription -Subscription $_.Name
    $vms = Get-AzVm -Status | Where-Object { $_.StorageProfile.OsDisk.OsType -eq ''Windows'' -and $_.PowerState -eq ''VM running'' }
    forEach ($vm in $vms) {
      $CSEvalidation = Get-AzVmExtension -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -ErrorAction Continue | Where-Object { $_.Extensiontype -like ''CustomScript*'' } 
      if ($CSEvalidation -ne $null) {
        $null = Remove-AzVmExtension -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -Name $CSEvalidation.name -Force -ErrorAction Continue
      }
      $null = Set-AzVMCustomScriptExtension -TypeHandlerVersion 1.10 `
        -ResourceGroupName $vm.resourceGroupName `
        -VMName $vm.Name `
        -FileName $fileName `
        -ContainerName $containerName `
        -StorageAccountName $storageAccountName `
        -StorageAccountKey $storageAccountKey `
        -Run $fileName `
        -Location ''West Europe'' `
        -Name ''CustomScriptExtension'' `
        -ErrorAction Continue
      $cseOutput = ((Get-AzVm -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -Status).Extensions | where { $_.Type -eq ''Microsoft.Compute.CustomScriptExtension'' }).SubStatuses.Message[0]
      
      # 构造并输出一个具有所需属性的 [pscustomobject] 实例。属性名称将成为 CSV 列名。
      [pscustomobject] @{
        VmName = $vm.Name
        CseSubstatus = $cseOutput
      }
    }
  } | 
  Export-Csv -Delimiter '';'' -NoTypeInformation -Path $(Pipeline.Workspace)\***.csv 

<details>
<summary>英文:</summary>
&lt;!-- language-all: sh --&gt;
**Update**: 
* *Hidden control characters* in the value of `$cseOutput` turned out to cause the problem, and eliminating them with `$cseOutput = $cseOutput -replace &#39;\W&#39;` solved it.
* Note that this specific regex-based [`-replace`](https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_Comparison_Operators#replacement-operator) operation removes all characters that aren&#39;t _word_ characters from the string, i.e. anything isn&#39;t either an alphanumeric character or `_`.
* To limit removal to _control characters_ and _hidden format characters_ only (see [Character classes in regular expressions](https://docs.microsoft.com/en-us/dotnet/standard/base-types/character-classes-in-regular-expressions#SupportedUnicodeGeneralCategories)), use:  
`$cseOutput = $cseOutput -replace &#39;[\p{Cc}\p{Cf}]&#39;` 
---
#### Original answer:
Your symptom is a bit of mystery: If the hashtable has multiple entries, you *should* see multiple rows, albeit with fixed column names `&quot;Name&quot;,&quot;Key&quot;,&quot;Value&quot;`; try with ` @{ one = 1; two = 2; three = 3 }.GetEnumerator() | ConvertTo-Csv` as a quick example.
---
&gt;  How should I modify script to get the result I want - being a CSV file with two columns - list of all vm names from all subscriptions and cse substatus message.
Note: **The question has since been updated to include the code below, with modifications.**
Emit `[pscustomobject]` instances with properties named for the desired CSV column names from your `foreach` loop and let PowerShell collect them in an array for you - or, preferable - switch to `ForEach-Object` and pipe those objects directly to `Export-Csv`:

  $null = Set-AzVMCustomScriptExtension -TypeHandlerVersion 1.10 `
-ResourceGroupName $vm.resourceGroupName `
-VMName $vm.Name `
-FileName $fileName `
-ContainerName $containerName `
-StorageAccountName $storageAccountName `
-StorageAccountKey $storageAccountKey `
-Run $fileName `
-Location 'West Europe' `
-Name 'CustomScriptExtension' `
-ErrorAction Continue
$cseOutput = ((Get-AzVm -VmName $vm.name -ResourceGroupName $vm.resourceGroupName -Status).Extensions | where { $_.Type -eq 'Microsoft.Compute.CustomScriptExtension' }).SubStatuses.Message[0]
# Construct and output a [pscustomobject] instance with the desired
# properties. The property names will become the CSV colum names.
[pscustomobject] @{
VmName = $vm.Name
CseSubstatus = $cseOutput
}
}

</details>