Question

我在文本文件中有这个XML文档：

<?xml version="1.0"?>
<Objects>
  <Object Type="System.Management.Automation.PSCustomObject">
    <Property Name="DisplayName" Type="System.String">SQL Server (MSSQLSERVER)</Property>
    <Property Name="ServiceState" Type="Microsoft.SqlServer.Management.Smo.Wmi.ServiceState">Running</Property>
  </Object>
  <Object Type="System.Management.Automation.PSCustomObject">
    <Property Name="DisplayName" Type="System.String">SQL Server Agent (MSSQLSERVER)</Property>
    <Property Name="ServiceState" Type="Microsoft.SqlServer.Management.Smo.Wmi.ServiceState">Stopped</Property>
  </Object>
</Objects>

我想遍历每个对象并找到DisplayName和ServiceState。我该怎么办？我已经尝试过各种各样的组合，并且正在努力解决这个问题。

我这样做是为了将XML变为变量：

[xml]$priorServiceStates = Get-Content $serviceStatePath;

其中$serviceStatePath是上面显示的xml文件名。然后我想我可以做类似的事情：

foreach ($obj in $priorServiceStates.Objects.Object)
{
    if($obj.ServiceState -eq "Running")
    {
        $obj.DisplayName;
    }
}

在这个例子中，我想要一个用SQL Server (MSSQLSERVER)

输出的字符串

Answer 1

PowerShell具有内置的XML和XPath功能。您可以将Select-Xml cmdlet与XPath查询一起使用，从而从XML对象中选择节点 .Node。'＃text'来访问节点值。

[xml]$xml = Get-Content $serviceStatePath
$nodes = Select-Xml "//Object[Property/@Name='ServiceState' and Property='Running']/Property[@Name='DisplayName']" $xml
$nodes | ForEach-Object {$_.Node.'#text'}

或更短

[xml]$xml = Get-Content $serviceStatePath
Select-Xml "//Object[Property/@Name='ServiceState' and Property='Running']/Property[@Name='DisplayName']" $xml |
  % {$_.Node.'#text'}

Answer 2

您也可以在没有[xml]强制转换的情况下执行此操作。（尽管xpath本身就是一个世界。https://www.w3schools.com/xml/xml_xpath.asp）

$xml = (select-xml -xpath / -path stack.xml).node
$xml.objects.object.property

或者仅此而已，xpath区分大小写。两者具有相同的输出：

$xml = (select-xml -xpath /Objects/Object/Property -path stack.xml).node
$xml


Name         Type                                                #text
----         ----                                                -----
DisplayName  System.String                                       SQL Server (MSSQLSERVER)
ServiceState Microsoft.SqlServer.Management.Smo.Wmi.ServiceState Running
DisplayName  System.String                                       SQL Server Agent (MSSQLSERVER)
ServiceState Microsoft.SqlServer.Management.Smo.Wmi.ServiceState Stopped

如何在Powershell中迭代XML？

2 个答案: