不要通过powershell命令将相同的条目添加到xml中

Question

我有一个XML文件，需要运行时节点下的条目（以红色突出显示）：

我可以通过以下PowerShell脚本实现此目的

$appFrameContainerAppConfig = 'D:\H.Infrastructure.AppFrame.Container.exe.config'
$doc = (Get-Content $appFrameContainerAppConfig) -as [Xml] 

$root = $doc.get_DocumentElement()

$newDependentAssembly = $doc.CreateElement("dependentAssembly")

$newAssemblyIdentity = $doc.CreateElement("assemblyIdentity")
$newAssemblyIdentity.SetAttribute("name","EntityFramework")
$newAssemblyIdentity.SetAttribute("publicKeyToken","b77a5c561934e089")
$newAssemblyIdentity.SetAttribute("culture","neutral")
$newDependentAssembly.AppendChild($newAssemblyIdentity)

$newCodeBase = $doc.CreateElement("codeBase")
$newCodeBase.SetAttribute("version","6.0.0.0")
$newCodeBase.SetAttribute("href","EntityFramework_6.1.3/EntityFramework.dll")
$newDependentAssembly.AppendChild($newCodeBase)

$root.runtime.assemblyBinding.AppendChild($newDependentAssembly)

$newDependentAssembly = $doc.CreateElement("dependentAssembly")

$newAssemblyIdentity = $doc.CreateElement("assemblyIdentity")
$newAssemblyIdentity.SetAttribute("name","EntityFramework.SqlServer")
$newAssemblyIdentity.SetAttribute("publicKeyToken","b77a5c561934e089")
$newAssemblyIdentity.SetAttribute("culture","neutral")
$newDependentAssembly.AppendChild($newAssemblyIdentity)

$newCodeBase = $doc.CreateElement("codeBase")
$newCodeBase.SetAttribute("version","6.0.0.0")
$newCodeBase.SetAttribute("href","EntityFramework_6.1.3/EntityFramework.SqlServer.dll")
$newDependentAssembly.AppendChild($newCodeBase)

$root.runtime.assemblyBinding.AppendChild($newDependentAssembly)

$newDependentAssembly = $doc.CreateElement("dependentAssembly")

$newAssemblyIdentity = $doc.CreateElement("assemblyIdentity")
$newAssemblyIdentity.SetAttribute("name","System.Data.SQLite")
$newAssemblyIdentity.SetAttribute("publicKeyToken","db937bc2d44ff139")
$newAssemblyIdentity.SetAttribute("culture","neutral")
$newDependentAssembly.AppendChild($newAssemblyIdentity)

$newCodeBase = $doc.CreateElement("codeBase")
$newCodeBase.SetAttribute("version","1.0.98.0")
$newCodeBase.SetAttribute("href","SQLite_1.0.98.1/System.Data.SQLite.dll")
$newDependentAssembly.AppendChild($newCodeBase)

$root.runtime.assemblyBinding.AppendChild($newDependentAssembly)

$newDependentAssembly = $doc.CreateElement("dependentAssembly")

$newAssemblyIdentity = $doc.CreateElement("assemblyIdentity")
$newAssemblyIdentity.SetAttribute("name","System.Data.SQLite.EF6")
$newAssemblyIdentity.SetAttribute("publicKeyToken","db937bc2d44ff139")
$newAssemblyIdentity.SetAttribute("culture","neutral")
$newDependentAssembly.AppendChild($newAssemblyIdentity)

$newCodeBase = $doc.CreateElement("codeBase")
$newCodeBase.SetAttribute("version","1.0.98.0")
$newCodeBase.SetAttribute("href","SQLite_1.0.98.1/System.Data.SQLite.EF6.dll")
$newDependentAssembly.AppendChild($newCodeBase)

$root.runtime.assemblyBinding.AppendChild($newDependentAssembly)

$newDependentAssembly = $doc.CreateElement("dependentAssembly")

$newAssemblyIdentity = $doc.CreateElement("assemblyIdentity")
$newAssemblyIdentity.SetAttribute("name","System.Data.SQLite.Linq")
$newAssemblyIdentity.SetAttribute("publicKeyToken","db937bc2d44ff139")
$newAssemblyIdentity.SetAttribute("culture","neutral")
$newDependentAssembly.AppendChild($newAssemblyIdentity)

$newCodeBase = $doc.CreateElement("codeBase")
$newCodeBase.SetAttribute("version","1.0.98.0")
$newCodeBase.SetAttribute("href","SQLite_1.0.98.1/System.Data.SQLite.Linq.dll")
$newDependentAssembly.AppendChild($newCodeBase)

$root.runtime.assemblyBinding.AppendChild($newDependentAssembly)
Write-Output $root.runtime.assemblyBinding.dependentAssembly
$doc.Save($appFrameContainerAppConfig)

我需要一个条件来评估XML中是否存在以红色突出显示的条目，如果是这样，请避免添加相同的条件。

if($root.SelectNodes('//configuration/runtime/assemblyBinding/dependentAssembly/assemblyIdentity[@name="EntityFramework"]')) {
} else {
}

我在这里使用的条件似乎不起作用。它不会进入，如果或其他条件。有什么建议吗？

Answer 1

检查<runtime>节点是否已包含条目，例如像这样：

if ($root.SelectNodes('//runtime/dependentAssembly').Count -eq 0) {
  ...
}

如果您需要更细致的检查，请调整XPath expression。

编辑：显然您的XML数据使用名称空间，因此您需要一个名称空间管理器来选择具有名称空间的节点：

$nsm = New-Object System.Xml.XmlNamespaceManager($doc.NameTable)
$nsm.AddNamespace('ns', 'urn:schemas-microsoft-com:asm.v1')
if ($doc.SelectNodes('//ns:assemblyBinding/dependentAssembly/assemblyIdentity[@name="EntityFramework"]', $nsm).Count -eq 0) {
  ...
}