How to: Enumerate All Instances of a Class (C#)

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This topic provides step-by-step instructions for enumerating the instances of a specified CIM class using the Windows Management Infrastructure (MI) .NET API. In addition to the steps, a full source code example is provided at the end of the topic.

Note

To see the native MI API and Microsoft Visual C++ version of this topic, refer to How to: Enumerate All Instances of a Class (C/C++)

 

Step-by-step Instructions

  1. Add a reference to the Microsoft.Management.Infrastructure reference assembly. (This assembly ships as part of the Windows Software Development Kit (SDK) for Windows 8.)

  2. Add a using statement for the Microsoft.Management.Infrastructure namespace.

    using Microsoft.Management.Infrastructure;

  3. Instantiate a CimSession object. The following snippet uses the standard "localhost" value for the CimSession.Create method.

    CimSession cimSession = CimSession.Create("localhost");

  4. Call the CimSession.EnumerateInstances method passing the desired CIM namespace and class whose instances you want to enumerate. The following snippet enumerates the instances of the Win32_Process class. (You'll need to add a using statement for the System.Collections.Generic namespace so that the compiler can locate the IEnumerable type information.)

    IEnumerable<CimInstance> enumeratedInstances = 
  cimSession.EnumerateInstances(@"root\cimv2", "Win32_Process");

  5. Loop through the returned CimInstance objects.

    foreach (CimInstance cimInstance in enumeratedInstances)
{ /* access desired CimInstance members */ }

Example

The following code sample enumerates all instances of the Win32_Process class (which represents active processes) on the local machine, and prints the name of each process.

Note

In a real application you would define as parameters the computer name ("localhost"), CIM namespace ("root\cimv2"), and class name ("Win32_Process"). For purposes of simplicity, these have been hardcoded in this example.

 

using System;
using System.Collections.Generic;
using Microsoft.Management.Infrastructure;

public partial class MI
{
    public static void EnumerateInstances()
    {
        try
        {
            CimSession cimSession = CimSession.Create("localhost");
            IEnumerable<CimInstance> enumeratedInstances = 
                cimSession.EnumerateInstances(@"root\cimv2", "Win32_Process");
            foreach (CimInstance cimInstance in enumeratedInstances)
            {
                Console.WriteLine("{0}", cimInstance.CimInstanceProperties["Name"].Value.ToString());
            }
        }
        catch (CimException ex) 
        { 
            // Handle the exception as appropriate.
            // This example prints the message.
            Console.WriteLine(ex.Message); 
        }
    }
}