Hard Drive Information with WMI

Josh Dycus

Hello,

I am trying to retrieve system information using WMI. Everything is working good until I got to the Hard Drive. I am trying to populate the Drive size for the local Hard Drives on the system. The issue is at runtime it only populate the first drive and does not go beyond that. I am still fairly new to C#. Here is the snippet for the Hard Drive:

public string GetHardDrive()
        {


            double disk = 0;
            ManagementObjectSearcher searcher = new ManagementObjectSearcher("root\\CIMV2",
                    "SELECT * FROM Win32_LogicalDisk where DriveType=3");
            foreach (ManagementObject wmi in searcher.Get())
            {
                try
                {
                     disk = Math.Round(((((double)Convert.ToDouble(wmi["Size"]) / 1024) / 1024) / 1024), 2);
                     return disk.ToString();
                }
                catch
                {
                }
            }
            return "Unable to Find Drive";
        }

Any Help would be appreciated.

Thanks in advance.

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sam Hobbs16y ago
Accepted answer
Does your catch block really look like that? If so then note that if there is an error, you will never know about the error. You should not use a catch block such as that to ignore errors unless you know for sure that there will be errors and you never need to know about the errors.

Look at your code. I really doubt that you want to use the return statement there, and I probably don't need to explain what I mean. Do you understand how the return statement causes the problem?
Josh Dycus16y ago
No Worries. You pointed me in the direction that I needed to come to the resolution. Thanks again!
Sam Hobbs16y ago
I am sorry that I did not see the problem sooner.
Josh Dycus16y ago
Thanks again for the response. My Catch block was only like that while I was making sure I could get this to work. I have modified it since I posted last. Thanks. Also I took a look at the return statement and I saw exactly what you were talking about. I moved it outside of the try/catch block and now it return all the type 3 drives. Here is the final code:

public string GetHardDrive()
        {
            double disk = 0;
            double free = 0;
            StringBuilder Drive = new StringBuilder();
                ManagementObjectSearcher searcher = new ManagementObjectSearcher("root\\CIMV2",
                        "SELECT * FROM Win32_LogicalDisk Where DriveType = 3");
                foreach (ManagementObject wmi in searcher.Get())
                {
                    try
                    {

                        disk = Math.Round(((((double)Convert.ToDouble(wmi["Size"]) / 1024) / 1024) / 1024), 2);
                        free = Math.Round(((((double)Convert.ToDouble(wmi["FreeSpace"]) / 1024) / 1024) / 1024), 2);
                        Drive.Append("Drive: " + wmi["Name"].ToString() + Environment.NewLine + "Total Size: " +
                            disk.ToString() + " GB" + Environment.NewLine + "Free Space: " + free.ToString() + " GB"
                            + Environment.NewLine + Environment.NewLine);
                    }
                    catch (ManagementException ex)
                    {
                        MessageBox.Show("There was an error in your Query" + ex.Message.ToString());
                    }
                }
                return Drive.ToString();
        }
Thanks for all the responses and help I appreciate it.
Mahesh Chand16y ago
You can direct use the DriveInfo class and its method.

This article gets all drives and lists on the console.

DriveInfo Class in C#
Josh Dycus16y ago
Thanks for the response. Sorry for the delay I had to get back to work to look. When you run the query is it only lists C: and it should list 2 other drives as well. I am using to the WMI Code Creator to assist and when you execute the code through the creator it displays all the drives just fine. Yes the other to drives are Drive type 3.
Sam Hobbs16y ago
What do you mean by populate? Do you mean that it returns more than one drive but does not provide the information or do you mean that it returns only one drive? If only one drive, are you sure that the additional drive(s) is(are) drive type 3?

Try issuing the query using WBEMTest; it is a tool that should be in your system somewhere. When you use it, first click on the Connect button then okay then click on the Query button.