Get Logical Drives Information

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• Download demo project - 7.39 Kb

Introduction

Getting information about logical drives might not be an easy task. Using managed code, one way to do this is by using the System.Management namespace.

Background

In order to create something reusable, I have wrapped this functionality in a DiskCollection class derived from CollectionBase. This collection acts as a class factory to create instances of a nested class called LogicalDriveInfo. Two indexers, one using the order and the other the drive letter will provide the read only information about the drives.

public LogicalDriveInfo this[int i]
{
    get
    {
        if(i >= disks.Count || i < 0)
            return null;
        else
            return (LogicalDriveInfo)disks[i];
    }
}

public LogicalDriveInfo this[char drive]
{
    get
    {
        if(char.IsLetter(drive))
            foreach(LogicalDriveInfo drinfo in disks)
                if(char.ToLower(drinfo.Name) == char.ToLower(drive))
                    return drinfo;
        return null;
    }
}

But the work horse of this collection is the Load() method that gets the information from the ManagementObject instances. Using two queries that target the mapped and the local disks, the disk's ArrayList is populated with LogicalDriveInfo instances.

//..............
using(ManagementObjectSearcher DiskSearch = 
                new ManagementObjectSearcher(new 
                  SelectQuery("Select * from Win32_LogicalDisk")))
{
    using(ManagementObjectCollection moDiskCollection = 
                                                 DiskSearch.Get())
    {
        foreach(ManagementObject mo in  moDiskCollection)
        {
            LogicalDriveInfo dskinfo = 
                                  new LogicalDriveInfo(mo ,false);
            if(this[dskinfo.Name] == null)
                 disks.Add(dskinfo);//new mapping
            mo.Dispose();
        }
    }
}
using(ManagementObjectSearcher ShareDiskSearch = 
                new ManagementObjectSearcher(new 
                  SelectQuery("Select * from Win32_MappedLogicalDisk")))
{
    using(ManagementObjectCollection moSharedDiskCollection = 
                                                  ShareDiskSearch.Get())
    {
        foreach(ManagementObject mo in  moSharedDiskCollection)
        {
            LogicalDriveInfo dskinfo = new LogicalDriveInfo(mo ,true);
            if(this[dskinfo.Name] == null)
            {
                disks.Add(dskinfo);
            }
            else
                this[dskinfo.Name].Shared = true;
            mo.Dispose();
        }
    }
}
//.................

You should be aware of the fact that you would need certain privileges to iterate the mapped disk collection. Another thing worth noting is the way we extract the information from the ManagementObject using an indexer:

internal LogicalDriveInfo(ManagementObject mo, bool shared)
{
    try
    {
        string txt = mo["Name"].ToString();
        if(txt.Length > 0)
            Name = txt[0];
        txt = mo["Volumeserialnumber"].ToString();

        if(txt.Length > 0)
            Volumeserialnumber = long.Parse(txt, 
                System.Globalization.NumberStyles.HexNumber);
            txt = mo["Size"].ToString();
            if(txt.Length > 0)
                Size = long.Parse(txt);

            Description = mo["Description"].ToString();
    }
    catch
    {
    }
    finally
    {
        Shared = shared;
    }            
}

Using the code

Using the previous collection class should be no surprise: we load it and then we populate the list control with data making use of its IEnumerator implementation.

//........
if(DiskColl == null)
    DiskColl = new DiskCollection();
if(!DiskColl.Load())
{
    MessageBox.Show(this,"Unable to retrieve disk info!");
    return;
}
DiskList.Items.Clear();
int i = 0;
foreach(DiskCollection.LogicalDriveInfo diskinfo in DiskColl)
{
    DiskList.Items.Add(diskinfo.Name.ToString(),i);
    DiskList.Items[i].SubItems.Add(diskinfo.Volumeserialnumber.ToString("x"));
    DiskList.Items[i].SubItems.Add(diskinfo.Size.ToString("d"));
    DiskList.Items[i].SubItems.Add(diskinfo.Shared.ToString());
    DiskList.Items[i].SubItems.Add(diskinfo.Description);
    i++;
}
//...............................

History

• This is version 1.0.