This documentation is archived and is not being maintained.

ManagementKeyAttribute Class

The ManagementKey attribute identifies the key properties of a WMI class.

Namespace:  System.Management.Instrumentation
Assembly:  System.Core (in System.Core.dll)

[AttributeUsageAttribute(AttributeTargets.Property|AttributeTargets.Field, AllowMultiple = false)]
[HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort = true)]
public sealed class ManagementKeyAttribute : ManagementMemberAttribute


The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

Unless a WMI class is a singleton, it can have multiple corresponding instances. Clients of the class must be able to uniquely identify the specific instance they are interested in. So, as a provider writer, you must choose a property or set of properties that uniquely identify an instance of each of your WMI classes. You use the ManagementKeyAttribute attribute to identify those key properties. Properties identified as keys have the same runtime behavior as read-only properties indicated by the ManagementProbeAttribute attribute.

The following example shows how to use the ManagementKeyAttribute to mark a field as a key property of a WMI class.

public int id;

The next example shows how to use the ManagementKeyAttribute attribute to mark a key property of a WMI class.


// Use the ManagementKey attribute to specify that this property 
// is used as the key identifier of this class and for the WMI
// instances of this class.  This property must be unique for each
// class instance.
public int Id
    get { return System.Diagnostics.Process.GetCurrentProcess().Id; }


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5