Windows Dev Center

Associating Instances Between Namespaces

An association view class allows you to use ASSOCIATORS OF queries on classes that reside in different namespaces.

The following procedure describes how to associate instances between namespaces.

Aa384790.wedge(en-us,VS.85).gifTo associate instances between namespaces

  1. Begin your class definition with the Association string qualifier.

    The JoinOn, Association, and Union qualifiers are mutually exclusive.

  2. Create the queries that define source instances used in the view class with the ViewSources qualifier.
  3. Define the names and location of the namespaces in which the source instances are located with the ViewSpaces qualifier.
  4. Define the properties you want in your association view class with the PropertySources qualifier.

    If necessary, you can tag any of the properties as belonging to a source class by using the HiddenDefault qualifier.

  5. Tag any relevant properties with the Direct qualifier.

    The Direct qualifier prevents the View Provider from mapping the tagged association reference to a view reference.

The following code examples show how to create association view classes.

[union,
ViewSources {"SELECT * FROM Win32_OperatingSystem"},
    ViewSpaces {"\\\\.\\root\\cimv2"},
    dynamic, provider("MS_VIEW_INSTANCE_PROVIDER")
]
class Union_OS_For_AssociationExample
{
    [key, PropertySources{"Name"}]
    string Name;

    [PropertySources{"Version"}]
    string Version;

    [PropertySources{"BuildNumber"}]
    string BuildNumber;
};

[
Association,
ViewSources {"SELECT * FROM Win32_SystemOperatingSystem"}, 
ViewSpaces {"\\\\.\\root\\cimv2"},
dynamic, provider("MS_VIEW_INSTANCE_PROVIDER")
]
class Association_SystemViewOperatingSystem
{
    [Direct, key, PropertySources{"GroupComponent"}]
    Win32_ComputerSystem ref Computer;
    
    [key, PropertySources{"PartComponent"}]
    Union_OS_For_AssociationExample ref OperatingSystem;
};

 

 

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