[c#] Get Hard disk serial Number

I have used the following method in a project and it's working successfully.

private string identifier(string wmiClass, string wmiProperty)
//Return a hardware identifier
{
    string result = "";
    System.Management.ManagementClass mc = new System.Management.ManagementClass(wmiClass);
    System.Management.ManagementObjectCollection moc = mc.GetInstances();
    foreach (System.Management.ManagementObject mo in moc)
    {
        //Only get the first one
        if (result == "")
        {
            try
            {
                result = mo[wmiProperty].ToString();
                break;
            }
            catch
            {
            }
        }
    }
    return result;
}

you can call the above method as mentioned below,

string modelNo = identifier("Win32_DiskDrive", "Model");
string manufatureID = identifier("Win32_DiskDrive", "Manufacturer");
string signature = identifier("Win32_DiskDrive", "Signature");
string totalHeads = identifier("Win32_DiskDrive", "TotalHeads");

If you need a unique identifier, use a combination of these IDs.