Question

尝试执行以下查询时，我不断收到“无效查询”异常：

ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT * FROM Win32_DiskQuota WHERE QuotaVolume.DeviceID = 'C:'");
ManagementObjectCollection quotaCollection = searcher.Get();

然而这有效：“SELECT * FROM Win32_DiskQuota”。

根据MSDN：

对于WHERE子句中类描述符的大多数用法，WMI标记了   查询无效并返回错误。但是，使用点（。）   WMI中类型为object的属性的运算符。例如，   如果Prop是MyClass的有效属性，则以下查询有效   类型对象：

SELECT * FROM MyClass WHERE Prop.embedprop = 5

这是否意味着仅当Prop声明为OBJECT时才有效？

以下是例外情况：

System.Management.ManagementException was unhandled
  HResult=-2146233087
  Message=Invalid query 
  Source=System.Management
  StackTrace:
       в System.Management.ManagementException.ThrowWithExtendedInfo(ManagementStatus errorCode)
       в System.Management.ManagementObjectCollection.ManagementObjectEnumerator.MoveNext()
       в UserQuota.Program.getQuota() в c:\users\administrator\documents\visual studio 2015\Projects\UserQuota\UserQuota\Program.cs:строка 40
       в UserQuota.Program.Main(String[] args) в c:\users\administrator\documents\visual studio 2015\Projects\UserQuota\UserQuota\Program.cs:строка 33
       в System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       в System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       в Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       в System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       в System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       в System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       в System.Threading.ThreadHelper.ThreadStart()
  InnerException:

Answer 1

是。根据{{3}}，QuotaVolume属性是对Win32_LogicalDisk WMI类的引用。您提供的MSDN引用了根据WQL规范查询无效的原因。

相反，您可以使用以下内容：

ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT * FROM Win32_DiskQuota WHERE QuotaVolume = \"Win32_LogicalDisk.DeviceID=\\\"C:\\\"\"");
ManagementObjectCollection quotaCollection = searcher.Get();

（注意所有逃脱......）

WMI .NET无效查询

1 个答案: