WMI and .NET

Introduction

Windows Management Instrumentation(WMI) Provides access to a rich set of management information and management events about the system, devices, and applications instrumented to the Windows Management Instrumentation (WMI) infrastructure. 

Objective

To understand about basics of WMI.

Using the code

We can read the logs with the help of Event Log class but when I tried to access remote server logs then it failed and started throwing an error. Using Event Log class we can access only local machine logs.

In order to access the remote server details we should use WMI.

WMI gives a way to .net developers to connect to remote machines and access of it.

With the help of WMI we can access remote machine details like event logs, disk space, services, printers, USB details etc.

Let’s try to understand WMI with simple example.

WMI classes reside under system.Management namespace.

 

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Xml.Linq;

using System.Management;

using System.Diagnostics;

using System.Collections;

 

namespace WMI

{

    class EventLogDetails

    {

        public string Message { get; set; }

        public string Type { get; set; }

        public DateTime TimeGenerated { get; set; }

        public string Category {get;set;}

        public string MachineName {get;set;}

        public string SourceName{get;set;}

        public DateTime TimeWritten{get;set;}

        public string User{get;set;}

        /// <summary>

        ///

        /// </summary>

        /// <returns></returns>

        public Dictionary<string, string> GetInfo()

        {

            //dictionary object to hold the values

            Dictionary<string, string> dictInfo = new Dictionary<string, string>();

            dictInfo.Add("Message", "");

            dictInfo.Add("Source", "");

            dictInfo.Add("Type ", "");

            dictInfo.Add("Category ", "");

            dictInfo.Add("TimeWritten", "");

            dictInfo.Add("MachineName", "");

            

            //create our WMI searcher

            ManagementPath mPath_EventLog;

            ManagementScope mgmtScope;

            ManagementObjectCollection moc;

            ManagementClass mc;

            ConnectionOptions options;

 

            System.Management.ObjectQuery qury = new ObjectQuery();

 

            string Host = "Machine Name";

            // Remote machine connection details

            options = new ConnectionOptions();

            options.Username = "UserName";

            options.Password = "Password";

            options.Authority = "ntlmdomain:" + " XYZ ";

            options.Authentication = AuthenticationLevel.PacketPrivacy;

            options.EnablePrivileges = true;

           //By default impersonation  is Impersonate

            options.Impersonation = ImpersonationLevel.Impersonate;

             mgmtScope = new ManagementScope("\\\\" + Host + "\\root\\cimv2", options);

            mPath_EventLog = new ManagementPath();

             //execute the query using WMI

            qury = new ObjectQuery("Select * from Win32_NTLogEvent

                  Where (Logfile = 'Application') AND (Type = 'Error')");

            ManagementObjectSearcher searcher = new ManagementObjectSearcher(mgmtScope, qury);

               //Create a XML doc

            var xdoc = new XDocument();

            XElement xroot = new XElement("root");

            xdoc.Add(xroot);

            //now loop through all the item found with the query

            foreach (ManagementObject obj in searcher.Get())

            {

                dictInfo = new Dictionary<string, string>();

                dictInfo ["Message"] = obj.Properties["Message"].Value.ToString();

                dictInfo ["Source"] = obj.Properties["Source"].Value.ToString();

                dictInfo ["Type"] = obj.Properties["Type"].Value.ToString();                                     dictInfo ["Category"] = obj.Properties["Category"].Value.ToString();

                dictInfo ["TimeWritten"] = obj.Properties["TimeWritten"].Value.ToString();

                dictInfo ["MachineName"] = obj.Properties["MachineName"].Value.ToString();

                xroot.Add(dictInfo.Select(ent => new XElement(ent.Key, ent.Value)));

               //Save the xml

                xdoc.Save("D:\\Test\\WMI.xml", SaveOptions.None);

            }

            //return the info

            return dictInfo;

        }       

 

    }

}

Now all the details will be saved in WMI.xml file. Next step is to retrieve the required information from xml and display it.

Conclusion

Have a fun with exploring WMI classesJ.

Please provide feedback below.

Reference

MSDN